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Discrete Packet Analysis for Improved Atmospheric Rejection on Modulated Laser Signals
O'Neill, M., McKenna, I., DiBenedetto, J., Capelle, G., Trainham, R.
This slide-show discusses how the method of discrete packet analysis improves atmospheric compensation for quasi-CW fluorescence detection methods. This is key to improving remote sensing capabilities.
HYPERsensarium : an archive of atmospheric conditions
Shaw, Kelly E. (Kelly Evelyn)
HYPERsensarium proposes a tangible interface of atmospheres for public experience through an archive of historical and projected weathers. While architecture's purpose has long been to act as the technical boundary between ...
atmospheric conditions influenced: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
to optical depth perturbations. In Earth-type atmospheres sustained planetary greenhouse effect with a stable ground surface temperature can only exist at a particular...
atmosphere conditions-an interdisciplinary: Topics by E-print...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
to optical depth perturbations. In Earth-type atmospheres sustained planetary greenhouse effect with a stable ground surface temperature can only exist at a particular...
atmospheric conditions controlling: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
to optical depth perturbations. In Earth-type atmospheres sustained planetary greenhouse effect with a stable ground surface temperature can only exist at a particular...
Standard 1D solar atmosphere as initial condition for MHD simulations and switch-on effects
Bourdin, Philippe-A
Many applications in Solar physics need a 1D atmospheric model as initial condition or as reference for inversions of observational data. The VAL atmospheric models are based on observations and are widely used since decades. Complementary to that, the FAL models implement radiative hydrodynamics and showed the shortcomings of the VAL models since almost equally long time. In this work, we present a new 1D layered atmosphere that spans not only from the photosphere to the transition region, but from the solar interior up to far in the corona. We also discuss typical mistakes that are done when switching on simulations based on such an initial condition and show how the initial condition can be equilibrated so that a simulation can start smoothly. The 1D atmosphere we present here served well as initial condition for HD and MHD simulations and should also be considered as reference data for solving inverse problems.
Description of Atmospheric Conditions at the Pierre Auger Observatory using the Global Data Assimilation System (GDAS)
Abreu, P.; /Lisbon, IST; Aglietta, M.; /Turin U. /INFN, Turin; Ahlers, M.; /Wisconsin U., Madison; Ahn, E.J.; /Fermilab; Albuquerque, I.F.M.; /Sao Paulo U.; Allard, D.; /APC, Paris; Allekotte, I.; /Buenos Aires, CONICET; Allen, J.; /New York U.; Allison, P.; /Ohio State U.; Almela, A.; /Natl. Tech. U., San Nicolas /Buenos Aires, CONICET; Alvarez Castillo, J.; /Mexico U., ICN /Santiago de Compostela U.
Atmospheric conditions at the site of a cosmic ray observatory must be known for reconstructing observed extensive air showers. The Global Data Assimilation System (GDAS) is a global atmospheric model predicated on meteorological measurements and numerical weather predictions. GDAS provides altitude-dependent profiles of the main state variables of the atmosphere like temperature, pressure, and humidity. The original data and their application to the air shower reconstruction of the Pierre Auger Observatory are described. By comparisons with radiosonde and weather station measurements obtained on-site in Malargue and averaged monthly models, the utility of the GDAS data is shown.
Graph-theoretic analysis of discrete-phase-space states for condition change detection and quantification of information
Hively, Lee M.
Data collected from devices and human condition may be used to forewarn of critical events such as machine/structural failure or events from brain/heart wave data stroke. By monitoring the data, and determining what values are indicative of a failure forewarning, one can provide adequate notice of the impending failure in order to take preventive measures. This disclosure teaches a computer-based method to convert dynamical numeric data representing physical objects (unstructured data) into discrete-phase-space states, and hence into a graph (structured data) for extraction of condition change.
OH-initiated oxidation of benzene Part I. Phenol formation under atmospheric conditions
OH-initiated oxidation of benzene Part I. Phenol formation under atmospheric conditions Rainer-radical initiated oxidation of benzene was studied in two simulation chambers: (1) the large-volume outdoor chamber-red spectroscopy (FTIR) were used to simultaneously measure phenol and benzene. The second study used only FTIR
Econometric Analysis of Discrete-Valued Irregularly-Spaced Financial Transactions Data Using a New Autoregressive Conditional Multinomial Model
Russell, Jeffrey; Engle, Robert F
Lancaster, T. , 1990, The Econometric Analysis of TransitionDEPARTMENT OF ECONOMICS ECONOMETRIC ANALYSIS OF DISCRETE-PAPER 98-10 APRIL 1998 Econometric analysis of discrete-
Influences of atmospheric conditions and air mass on the ratio of ultraviolet to total solar radiation
Riordan, C.J.; Hulstrom, R.L.; Myers, D.R.
The technology to detoxify hazardous wastes using ultraviolet (UV) solar radiation is being investigated by the DOE/SERI Solar Thermal Technology Program. One of the elements of the technology evaluation is the assessment and characterization of UV solar radiation resources available for detoxification processes. This report describes the major atmospheric variables that determine the amount of UV solar radiation at the earth's surface, and how the ratio of UV-to-total solar radiation varies with atmospheric conditions. These ratios are calculated from broadband and spectral solar radiation measurements acquired at SERI, and obtained from the literature on modeled and measured UV solar radiation. The following sections discuss the atmospheric effects on UV solar radiation and provide UV-to-total solar radiation ratios from published studies, as well as measured values from SERI's data. A summary and conclusions are also given.
Sulfur capture by oil shale ashes under atmospheric and pressurized FBC conditions
Yrjas, K.P.; Hupa, M. [Aabo Akademi Univ., Turku (Finland). Dept. of Chemical Engineering; Kuelaots, I.; Ots, A. [Tallinn Technical Univ. (Estonia). Thermal Engineering Dept.
When oil shale contains large quantities of limestone, a significant auto-absorption of sulfur is possible under suitable conditions. The sulfur capture by oil shale ashes has been studied using a pressurized thermogravimetric apparatus. The chosen experimental conditions were typical for atmospheric and pressurized fluidized bed combustion. The Ca/S molar ratios in the two oil shales studied were 8 (Estonian) and 10 (Israeli). The samples were first burned in a gas atmosphere containing O{sub 2} and N{sub 2} (and CO{sub 2} if pressurized). After the combustion step, SO{sub 2} was added and sulfation started. The results with the oil shales were compared to those obtained with an oil shale cyclone ash from the Narva power plant in Estonia. In general, the results from the sulfur capture experiments under both atmospheric and pressurized conditions showed that the oil shale cannot only capture its own sulfur but also significant amounts of additional sulfur of another fuel if the fuels are mixed together. For example from the runs at atmospheric pressure, the conversion of CaO to CaSO{sub 4} was about 70% for Israeli oil shale and about 55% for Estonian oil shale (850 C). For the cyclone ash the corresponding conversion was about 20%. In comparison it could be mentioned that under the same conditions the conversions of natural limestones are about 30%. The reason the cyclone ash was a poor sulfur absorbent was probably due to its temperature history. In Narva the oil shale was burned at a significantly higher temperature (1,400 C) than was used in the experiments (750 C and 850 C). This caused the ash to sinter and the reactive surface area of the cyclone ash was therefore decreased.
Measurements near the Atmospheric Surface Flux Group tower at SHEBA: Near-surface conditions and surface energy budget
Persson, Ola
Group tower at SHEBA: Near-surface conditions and surface energy budget, J. Geophys. Res., 107(C10Measurements near the Atmospheric Surface Flux Group tower at SHEBA: Near-surface conditions and surface energy budget P. Ola G. Persson,1 Christopher W. Fairall,2 Edgar L. Andreas,3 Peter S. Guest,4
Remote Raman - laser induced breakdown spectroscopy (LIBS) geochemical investigation under Venus atmospheric conditions
Clegg, Sanuel M [Los Alamos National Laboratory; Barefield, James E [Los Alamos National Laboratory; Humphries, Seth D [Los Alamos National Laboratory; Wiens, Roger C [Los Alamos National Laboratory; Vaniman, D. T. [Los Alamos National Laboratory; Sharma, S. K. [UNIV OF HAWAII; Misra, A. K. [UNIV OF HAWAII; Dyar, M. D. [MT. HOLYOKE COLLEGE; Smrekar, S. E. [JET PROPULSION LAB.
The extreme Venus surface temperatures ({approx}740 K) and atmospheric pressures ({approx}93 atm) create a challenging environment for surface missions. Scientific investigations capable of Venus geochemical observations must be completed within hours of landing before the lander will be overcome by the harsh atmosphere. A combined remote Raman - LIBS (Laser Induced Breakdown Spectroscopy) instrument is capable of accomplishing the geochemical science goals without the risks associated with collecting samples and bringing them into the lander. Wiens et al. and Sharma et al. demonstrated that both analytical techniques can be integrated into a single instrument capable of planetary missions. The focus of this paper is to explore the capability to probe geologic samples with Raman - LIBS and demonstrate quantitative analysis under Venus surface conditions. Raman and LIBS are highly complementary analytical techniques capable of detecting both the mineralogical and geochemical composition of Venus surface materials. These techniques have the potential to profoundly increase our knowledge of the Venus surface composition, which is currently limited to geochemical data from Soviet Venera and VEGA landers that collectively suggest a surface composition that is primarily tholeiitic basaltic with some potentially more evolved compositions and, in some locations, K-rich trachyandesite. These landers were not equipped to probe the surface mineralogy as can be accomplished with Raman spectroscopy. Based on the observed compositional differences and recognizing the imprecise nature of the existing data, 15 samples were chosen to constitute a Venus-analog suite for this study, including five basalts, two each of andesites, dacites, and sulfates, and single samples of a foidite, trachyandesite, rhyolite, and basaltic trachyandesite under Venus conditions. LIBS data reduction involved generating a partial least squares (PLS) model with a subset of the rock powder standards to quantitatively determine the major elemental abundance of the remaining samples. PLS analysis suggests that the major element compositions can be determined with root mean square errors ca. 5% (absolute) for SiO{sub 2}, Al{sub 2}O{sub 3}, Fe{sub 2}O{sub 3}(total), MgO, and CaO, and ca. 2% or less for TiO{sub 2}, Cr{sub 2}O{sub 3}, MnO, K{sub 2}O, and Na{sub 2}O. Finally, the Raman experiments have been conducted under supercritical CO{sub 2} involving single-mineral and mixed-mineral samples containing talc, olivine, pyroxenes, feldspars, anhydrite, barite, and siderite. The Raman data have shown that the individual minerals can easily be identified individually or in mixtures.
Comparison of optical emission from nanosecond and femtosecond laser produced plasma in atmosphere and vacuum conditions
Harilal, S. S.
occur during the laser pulse in ns laser ablation, fs laser pulses are too short that these phenomena doComparison of optical emission from nanosecond and femtosecond laser produced plasma in atmosphere Laser-induced breakdown spectroscopy Laser-produced plasma Plasma dynamics Femtosecond laser ablation
Effect of atmospheric conditions on operation of terahertz systems for remote detection of ionizing materials
Nusinovich, Gregory S.; Kashyn, Dmytro G. [IREAP, University of Maryland, College Park, Maryland 20742-3511 (United States)] [IREAP, University of Maryland, College Park, Maryland 20742-3511 (United States); Tatematsu, Yoshinori; Idehara, Toshitaka [FIR Center, University of Fukui, Fukui 910-8507 (Japan)] [FIR Center, University of Fukui, Fukui 910-8507 (Japan)
This study was motivated by a new concept of remote detection of concealed radioactive materials by using a high power terahertz (THz) wave beam, which can be focused in a small spot where the wave electric field exceeds the breakdown threshold. In the presence of seed electrons in such a volume, this focusing can initiate the avalanche breakdown. Typically, an ambient density of free electrons is assumed to be at the level of one particle per cubic centimeter. So, when a breakdown-prone volume is smaller than 1 cm{sup 3}, there should be significant difference between the breakdown rates in the case of presence of additional sources of ionization versus its absence. Since the flux density of gamma rays emitted by radioactive materials rapidly falls with the distance from the source, while the intensity of THz waves also decreases with the distance due to wave attenuation in the atmosphere, it is important to find an optimal location of the breakdown to be initiated for a given distance between a radioactive material and a THz antenna. This problem is analyzed in a given paper with the account for not only atmospheric attenuation of THz waves but also the air turbulence.
Microwave plasma based single step method for free standing graphene synthesis at atmospheric conditions
Tatarova, E.; Henriques, J.; Dias, A.; Ferreira, C. M. [Institute of Plasmas and Nuclear Fusion, Instituto Superior T�cnico, Technical University of Lisbon (Portugal)] [Institute of Plasmas and Nuclear Fusion, Instituto Superior T�cnico, Technical University of Lisbon (Portugal); Luhrs, C. C.; Phillips, J. [Department of Mechanical and Aerospace Engineering, Naval Postgraduate School, Monterey, California 93943 (United States)] [Department of Mechanical and Aerospace Engineering, Naval Postgraduate School, Monterey, California 93943 (United States); Abrashev, M. V. [Faculty of Physics, Sofia University, 1164 Sofia (Bulgaria)] [Faculty of Physics, Sofia University, 1164 Sofia (Bulgaria)
Microwave atmospheric pressure plasmas driven by surface waves were used to synthesize graphene sheets from vaporized ethanol molecules carried through argon plasma. In the plasma, ethanol decomposes creating carbon atoms that form nanostructures in the outlet plasma stream, where external cooling/heating was applied. It was found that the outlet gas stream temperature plays an important role in the nucleation processes and the structural quality of the produced nanostructures. The synthesis of few layers (from one to five) graphene has been confirmed by high-resolution transmission electron microscopy. Raman spectral studies were conducted to determine the ratio of the 2D to G peaks (>2). Disorder D-peak to G-peak intensity ratio decreases when outlet gas stream temperature decreases.
Fluidized bed pyrolysis of bitumen-impregnated sandstone at sub-atmospheric conditions
Fletcher, J.V.; Deo, M.D.; Hanson, F.V.
A 15.2 cm diameter fluidized bed reactor was designed, built, and operated to study the pyrolysis of oil sands at pressures slightly less than atmospheric. Fluidizing gas flow through the reactor was caused by reducing the pressure above the bed with a gas pump operating in the vacuum mode. Pyrolysis energy was supplied by a propane burner, and the hot propane combustion gases were used for fluidization. The fluidized bed pyrolysis at reduced pressure using combustion gases allowed the reactor to be operated at significantly lower temperatures than previously reported. At 450{degree}, over 80% of the bitumen fed was recovered as a liquid product, and the spent sand contained less than 1% coke. The liquid product recovery system, by design, yielded three liquid streams with distinctly different properties.
Fluidized bed pyrolysis of bitumen-impregnated sandstone at sub-atmospheric conditions
Fletcher, J.V.; Deo, M.D.; Hanson, F.V.
A 15.2 cm diameter fluidized bed reactor was designed, built, and operated to study the pyrolysis of oil sands at pressures slightly less than atmospheric. Fluidizing gas flow through the reactor was caused by reducing the pressure above the bed with a gas pump operating in the vacuum mode. Pyrolysis energy was supplied by a propane burner, and the hot propane combustion gases were used for fluidization. The fluidized bed pyrolysis at reduced pressure using combustion gases allowed the reactor to be operated at significantly lower temperatures than previously reported. At 450[degree], over 80% of the bitumen fed was recovered as a liquid product, and the spent sand contained less than 1% coke. The liquid product recovery system, by design, yielded three liquid streams with distinctly different properties.
Smith, C.; Brigmon, R.
Legionnaires disease is a pneumonia caused by the inhalation of the bacterium Legionella pneumophila. The majority of illnesses have been associated with cooling towers since these devices can harbor and disseminate the bacterium in the aerosolized mist generated by these systems. Historically, Savannah River Site (SRS) cooling towers have had occurrences of elevated levels of Legionella in all seasons of the year and in patterns that are difficult to predict. Since elevated Legionella in cooling tower water are a potential health concern a question has been raised as to the best control methodology. In this work we analyze available chemical, biological, and atmospheric data to determine the best method or key parameter for control. The SRS 4Q Industrial Hygiene Manual, 4Q-1203, 1 - G Cooling Tower Operation and the SRNL Legionella Sampling Program, states that 'Participation in the SRNL Legionella Sampling Program is MANDATORY for all operating cooling towers'. The resulting reports include L. pneumophila concentration information in cells/L. L. pneumophila concentrations >10{sup 7} cells/L are considered elevated and unsafe so action must be taken to reduce these densities. These remedial actions typically include increase biocide addition or 'shocking'. Sometimes additional actions are required if the problem persists including increase tower maintenance (e.g. cleaning). Evaluation of 14 SRS cooling towers, seven water quality parameters, and five Legionella serogroups over a three-plus year time frame demonstrated that cooling tower water Legionella densities varied widely though out this time period. In fact there was no one common consistent significant variable across all towers. The significant factors that did show up most frequently were related to suspended particulates, conductivity, pH, and dissolved oxygen, not chlorine or bromine as might be expected. Analyses of atmospheric data showed that there were more frequent significant elevated Legionella concentrations when the dew point temperature was high--a summertime occurrence. However, analysis of the three years of Legionella monitoring data of the 14 different SRS Cooling Towers demonstrated that elevated concentrations are observed at all temperatures and seasons. The objective of this study is to evaluate the ecology of L. pneumophila including serogroups and population densities, chemical, and atmospheric data, on cooling towers at SRS to determine whether relationships exist among water chemistry, and atmospheric conditions. The goal is to more fully understand the conditions which inhibit or encourage L. pneumophila growth and supply this data and associated recommendations to SRS Cooling Tower personnel for improved management of operation. Hopefully this information could then be used to help control L. pneumophila growth more effectively in SRS cooling tower water.
Effects of atmospheric conditions and control surface deflections on vortex characteristics
Shenkir, Calvin Edward
'lDITIONS AND CONTIIOL SURFACE DFFLFCTIONS ON 'JORTEX CHARACTERISTICS A Thesis by CALVIN EDLIARD 'HENlXIR, DR, Approved as to sty1e and content by: (Chairman of Committee) (Head 0; Depart;nant) f "1 {l'leniber ) Hay 197R !TSSIRACT Fffects of !". I. ;os, -'" I...-ic Conditions and Coriti. o1 SLI. Face Deil ections on Vot- ex CI1!?racieristics ('Iay 1972) Calvin Fd', 'at-d Shenkir, dr. , B. S. , Texas (t&il Univei sity rDII ected by: Dr. Charles I(, Rode it rger Large transpor t airp1aiic. s such as the Roe I'Ig 7II...
Griffith, Caitlin A.; Penteado, Paulo [Department of Planetary Sciences, University of Arizona, Tucson, AZ 85719 (United States); Rodriguez, Sebastien [Laboratoire AIM, Universite Paris 7/CNRS/CEA-Saclay, DSM/IRFU/SAp (France); Le Mouelic, Stephane [Laboratoire de Planetologie et Geodynamique, CNRS, UMR-6112, Universite de Nantes, 44000 Nantes (France); Baines, Kevin H.; Buratti, Bonnie; Sotin, Christophe [Jet Propulsion Laboratory, Pasadena, CA 91109 (United States); Clark, Roger [U.S. Geological Survey, Denver, CO 80225 (United States); Nicholson, Phil [Department of Astronomy, Cornell University, Ithaca, NY (United States); Jaumann, Ralf [Institute of Planetary Exploration, Deutsche Zentrum, fuer Luft- und Raumfahrt (Germany)
Images of Titan's clouds, possible over the past 10 years, indicate primarily discrete convective methane clouds near the south and north poles and an immense stratiform cloud, likely composed of ethane, around the north pole. Here we present spectral images from Cassini's Visual Mapping Infrared Spectrometer that reveal the increasing presence of clouds in Titan's tropical atmosphere. Radiative transfer analyses indicate similarities between summer polar and tropical methane clouds. Like their southern counterparts, tropical clouds consist of particles exceeding 5 {mu}m. They display discrete structures suggestive of convective cumuli. They prevail at a specific latitude band between 8 deg. - 20 deg. S, indicative of a circulation origin and the beginning of a circulation turnover. Yet, unlike the high latitude clouds that often reach 45 km altitude, these discrete tropical clouds, so far, remain capped to altitudes below 26 km. Such low convective clouds are consistent with the highly stable atmospheric conditions measured at the Huygens landing site. Their characteristics suggest that Titan's tropical atmosphere has a dry climate unlike the south polar atmosphere, and despite the numerous washes that carve the tropical landscape.
Observations of Secondary Organic Aerosol Production and Soot Aging under Atmospheric Conditions Using a Novel Environmental Aerosol Chamber
Glen, Crystal
of the processes leading to SOA production under ambient gaseous and particulate concentrations as well as the impact these aerosol types have on climate is poorly understood. Although the majority of atmospheric aerosols scatter radiation either directly...
Adding Complex Terrain and Stable Atmospheric Condition Capability to the Simulator for On/Offshore Wind Farm Applications (SOWFA) (Presentation)
Churchfield, M. J.
This presentation describes changes made to NREL's OpenFOAM-based wind plant aerodynamics solver so that it can compute the stably stratified atmospheric boundary layer and flow over terrain. Background about the flow solver, the Simulator for Off/Onshore Wind Farm Applications (SOWFA) is given, followed by details of the stable stratification/complex terrain modifications to SOWFA, along with some preliminary results calculations of a stable atmospheric boundary layer and flow over a simple set of hills.
Using Mesoscale Weather Model Output as Boundary Conditions for Atmospheric Large-Eddy Simulations and Wind-Plant Aerodynamic Simulations (Presentation)
Churchfield, M. J.; Michalakes, J.; Vanderwende, B.; Lee, S.; Sprague, M. A.; Lundquist, J. K.; Moriarty, P. J.
Wind plant aerodynamics are directly affected by the microscale weather, which is directly influenced by the mesoscale weather. Microscale weather refers to processes that occur within the atmospheric boundary layer with the largest scales being a few hundred meters to a few kilometers depending on the atmospheric stability of the boundary layer. Mesoscale weather refers to large weather patterns, such as weather fronts, with the largest scales being hundreds of kilometers wide. Sometimes microscale simulations that capture mesoscale-driven variations (changes in wind speed and direction over time or across the spatial extent of a wind plant) are important in wind plant analysis. In this paper, we present our preliminary work in coupling a mesoscale weather model with a microscale atmospheric large-eddy simulation model. The coupling is one-way beginning with the weather model and ending with a computational fluid dynamics solver using the weather model in coarse large-eddy simulation mode as an intermediary. We simulate one hour of daytime moderately convective microscale development driven by the mesoscale data, which are applied as initial and boundary conditions to the microscale domain, at a site in Iowa. We analyze the time and distance necessary for the smallest resolvable microscales to develop.
Analysis and experimental study on formation conditions of large-scale barrier-free diffuse atmospheric pressure air plasmas in repetitive pulse mode
Li, Lee, E-mail: email@example.com; Liu, Lun; Liu, Yun-Long; Bin, Yu; Ge, Ya-Feng; Lin, Fo-Chang [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electric and Electronic Engineering, HuaZhong University of Science and Technology (HUST), Wuhan 430074 (China)
Atmospheric air diffuse plasmas have enormous application potential in various fields of science and technology. Without dielectric barrier, generating large-scale air diffuse plasmas is always a challenging issue. This paper discusses and analyses the formation mechanism of cold homogenous plasma. It is proposed that generating stable diffuse atmospheric plasmas in open air should meet the three conditions: high transient power with low average power, excitation in low average E-field with locally high E-field region, and multiple overlapping electron avalanches. Accordingly, an experimental configuration of generating large-scale barrier-free diffuse air plasmas is designed. Based on runaway electron theory, a low duty-ratio, high voltage repetitive nanosecond pulse generator is chosen as a discharge excitation source. Using the wire-electrodes with small curvature radius, the gaps with highly non-uniform E-field are structured. Experimental results show that the volume-scaleable, barrier-free, homogeneous air non-thermal plasmas have been obtained between the gap spacing with the copper-wire electrodes. The area of air cold plasmas has been up to hundreds of square centimeters. The proposed formation conditions of large-scale barrier-free diffuse air plasmas are proved to be reasonable and feasible.
Fabrication of ZnO/Cu2O heterojunctions in atmospheric conditions: improved interface quality and solar cell performance
Ievskaya, Y.; Hoye, R. L. Z.; Sadhanala, A.; Musselman, K.; MacManus-Driscoll, J. L.
tail (Early view), Adv. Energy Mater. (2014). [8] A.J. Kronemeijer, V. Pecunia, D. Venkateshvaran, M. Nikolka, A. Sadhanala, J. Moriarty, M. Szumilo, H. Sirringhaus, Two-dimensional carrier distribution in top-gate polymer field-effect transistors... conditions and (b) optimized conditions of ZnO AALD deposition. Multiple whisker-, rod- and flower-like formations are present in the standard device. 0.1 0.2 0.3 0.4 0.5 ?8 ?7 ?6 ?5 ?4 ?3 ?2 ?1 0 Voltage V / V C ur re nt d en si ty J / m A cm ?2...
Scientific uncertainties in atmospheric mercury models III: Boundary and initial conditions, model grid resolution, and Hg(II) reduction mechanism
Lin, Che-Jen [ORNL; Pongprueksa, Pruek [Lamar University; Lindberg, Steven Eric [ORNL; Jang, Carey [U.S. Environmental Protection Agency, Raleigh, North Carolina; Braverman, Thomas [U.S. Environmental Protection Agency, Raleigh, North Carolina; Bullock, Russell O [NOAA; Ho, Thomas [ORNL; Chu, Hsing-Wei [Lamar University
In this study, the model response in terms of simulated mercury concentration and deposition to boundary condition (BC), initial condition (IC), model grid resolution (12 km versus 36 km), and two alternative Hg(II) reduction mechanisms, was investigated. The model response to the change of gaseous elemental mercury (GEM) concentration from 0 to 2 ngm3 in IC/BC is found to be very linear (r240.99) based on the results of sensitivity simulations in July 2001. An increase of 1 ngm3 of GEM in BC resulted in an increase of 0.81 ngm3 in the monthly average of total mercury concentration, and 1270 ngm2 in the monthly total deposition. IC has similar but weaker effects compared to those of BC. An increase of 1 ngm3 of GEM in IC resulted in an increase of 0.14 ngm3 in the monthly average of total mercury concentration, and 250 ngm2 in the monthly total deposition. Varying reactive gaseous mercury (RGM) or particulate mercury (PHg) in BC/IC has much less significant impact. Simulation results at different grid resolutions show good agreement (slope 0.950 1.026, r 0.816 0.973) in mercury concentration, dry deposition, and total deposition. The agreement in wet deposition is somewhat weaker (slope 0.770 0.794, r 0.685 0.892) due to the difference in emission dilution and simulated precipitation that subsequently change reaction rates in the aqueous phase. Replacing the aqueous Hg(II)-HO2 reduction by either RGM reduction by CO (51018cm3 molecule1 s1) or photoreduction of RGM (1105 s1) gives significantly better model agreement with the wet deposition measured by Mercury Deposition Network (MDN). Possible ranges of the reduction rates are estimated based on model sensitivity results. The kinetic estimate requires further verification by laboratory studies.
Farfan, E.; Jannik, T.
When assessing the feasibility of remediation following the detonation of a radiological dispersion device or improvised nuclear device in a large city, several issues should be considered including the levels and characteristics of the radioactive contamination, the availability of resources required for decontamination, and the planned future use of the city's structures and buildings. Currently, little is known about radionuclide penetration into construction materials in an urban environment. Knowledge in this area would be useful when considering costs of a thorough decontamination of buildings, artificial structures, and roads in an affected urban environment. Pripyat, a city substantially contaminated by the Chernobyl Nuclear Power Plant accident in April 1986, may provide some answers. The main objective of this study was to assess the depth of {sup 90}Sr and {sup 137}Cs penetration into reinforced concrete structures in a highly contaminated urban environment under natural weather conditions. Thirteen reinforced concrete core samples were obtained from external surfaces of a contaminated building in Pripyat. The concrete cores were drilled to obtain sample layers of 0-5, 5-10, 10-15, 15-20, 20-30, 30-40, and 40-50 mm. Both {sup 90}Sr and {sup 137}Cs were detected in the entire 0-50 mm profile of the reinforced cores sampled. In most of the cores, over 90% of the total {sup 137}Cs inventory and 70% of the total {sup 90}Sr inventory was found in the first 0-5 mm layer of the reinforced concrete. {sup 90}Sr had penetrated markedly deeper into the reinforced concrete structures than {sup 137}Cs.
optimization of discrete control systems with varying structure
(in russian). 4. Mansimov, K.B., Maharramov, Sh.F.: Necessary conditions of optimality for discrete system with variable structure and rolling right end of the path.
Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models
Daniels, Megan Hanako
groundwater, land-surface, and mesoscale atmospheric model-and modification of mesoscale circulations. , Mon. Wea.J. Davis, The effects of mesoscale surface heterogeneity on
Atmospheric optical calibration system
Hulstrom, Roland L. (Bloomfield, CO); Cannon, Theodore W. (Golden, CO)
An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions.
Atmospheric optical calibration system
Hulstrom, R.L.; Cannon, T.W.
An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions. 7 figs.
Morris, J; Johnson, S
The Distinct Element Method (also frequently referred to as the Discrete Element Method) (DEM) is a Lagrangian numerical technique where the computational domain consists of discrete solid elements which interact via compliant contacts. This can be contrasted with Finite Element Methods where the computational domain is assumed to represent a continuum (although many modern implementations of the FEM can accommodate some Distinct Element capabilities). Often the terms Discrete Element Method and Distinct Element Method are used interchangeably in the literature, although Cundall and Hart (1992) suggested that Discrete Element Methods should be a more inclusive term covering Distinct Element Methods, Displacement Discontinuity Analysis and Modal Methods. In this work, DEM specifically refers to the Distinct Element Method, where the discrete elements interact via compliant contacts, in contrast with Displacement Discontinuity Analysis where the contacts are rigid and all compliance is taken up by the adjacent intact material.
XXZ scalar products, Miwa variables and discrete KP
O. Foda; G. Schrader
We revisit the quantum/classical integrable model correspondence in the context of inhomogeneous finite length XXZ spin-1/2 chains with periodic boundary conditions and show that the Bethe scalar product of an arbitrary state and a Bethe eigenstate is a discrete KP tau-function. The continuous Miwa variables of discrete KP are the rapidities of the arbitrary state.
A discrete fractional random transform
Zhengjun Liu; Haifa Zhao; Shutian Liu
We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.
Discrete Fourier Transform Javier Montoya
Giger, Christine
Discrete Fourier Transform Javier Montoya Photogrammetry and Remote Sensing ETH Zurich March 16, 2012 1 Introduction The Discrete form of the Fourier transform is known as Discrete Fourier Transform domain using the Inverse Discrete Fourier Transform (IDFT): f(x) = 1 N N-1 x=0 F(u)ej 2 N ux for u = 0, 1
Thomas K. Gaisser
This paper is a brief overview of the theory and experimental data of atmospheric neutrino production at the fiftieth anniversary of the experimental discovery of neutrinos.
Differential Geometry: Discrete Exterior Calculus
Kazhdan, Michael
Differential Geometry: Discrete Exterior Calculus [Build Your Own DEC at Home. Elcott et al., 2006] [Discrete Differential Forms for Computational Modeling. Desbrun et al., 2005] [Discrete Exterior Calculus-simplices in : where c is a real-valued function. The space of k-chains is denoted Ck(). = k cc )( #12;Chains
L. R. G. Fontes; C. M. Newman; K. Ravishankar; E. Schertzer
The dynamical discrete web (DDW), introduced in recent work of Howitt and Warren, is a system of coalescing simple symmetric one-dimensional random walks which evolve in an extra continuous dynamical parameter s. The evolution is by independent updating of the underlying Bernoulli variables indexed by discrete space-time that define the discrete web at any fixed s. In this paper, we study the existence of exceptional (random) values of s where the paths of the web do not behave like usual random walks and the Hausdorff dimension of the set of such exceptional s. Our results are motivated by those about exceptional times for dynamical percolation in high dimension by H\\"aggstrom, Peres and Steif, and in dimension two by Schramm and Steif. The exceptional behavior of the walks in DDW is rather different from the situation for dynamical random walks of Benjamini, H\\"aggstrom, Peres and Steif. In particular, we prove that there are exceptional values of s for which the walk from the origin S^s(n) has limsup S^s(n)/\\sqrt n \\leq K with a nontrivial dependence of the Hausdorff dimension on K. We also discuss how these and other results extend to the dynamical Brownian web, a natural scaling limit of DDW. The scaling limit is the focus of a paper in preparation; it was studied by Howitt and Warren and is related to the Brownian net of Sun and Swart.
Hirsch, M.; Morisi, S.; Peinado, E.; Valle, J. W. F. [AHEP Group, Institut de Fisica Corpuscular--C.S.I.C./Universitat de Valencia, Edificio Institutos de Paterna, Apartado 22085, E-46071 Valencia (Spain)
We propose a new motivation for the stability of dark matter (DM). We suggest that the same non-Abelian discrete flavor symmetry which accounts for the observed pattern of neutrino oscillations, spontaneously breaks to a Z{sub 2} subgroup which renders DM stable. The simplest scheme leads to a scalar doublet DM potentially detectable in nuclear recoil experiments, inverse neutrino mass hierarchy, hence a neutrinoless double beta decay rate accessible to upcoming searches, while {theta}{sub 13}=0 gives no CP violation in neutrino oscillations.
Thermodynamics of discrete quantum processes
Janet Anders; Vittorio Giovannetti
We define thermodynamic configurations and identify two primitives of discrete quantum processes between configurations for which heat and work can be defined in a natural way. This allows us to uncover a general second law for any discrete trajectory that consists of a sequence of these primitives, linking both equilibrium and non-equilibrium configurations. Moreover, in the limit of a discrete trajectory that passes through an infinite number of configurations, i.e. in the reversible limit, we recover the saturation of the second law. Finally, we show that for a discrete Carnot cycle operating between four configurations one recovers Carnot's thermal efficiency.
Ilka Brunner; Nils Carqueville; Daniel Plencner
Orbifolding two-dimensional quantum field theories by a symmetry group can involve a choice of discrete torsion. We apply the general formalism of `orbifolding defects' to study and elucidate discrete torsion for topological field theories. In the case of Landau-Ginzburg models only the bulk sector had been studied previously, and we re-derive all known results. We also introduce the notion of `projective matrix factorisations', show how they naturally describe boundary and defect sectors, and we further illustrate the efficiency of the defect-based approach by explicitly computing RR charges. Roughly half of our results are not restricted to Landau-Ginzburg models but hold more generally, for any topological field theory. In particular we prove that for a pivotal bicategory, any two objects of its orbifold completion that have the same base are orbifold equivalent. Equivalently, from any orbifold theory (including those based on nonabelian groups) the original unorbifolded theory can be obtained by orbifolding via the `quantum symmetry defect'.
Description and validation of ERAD: An atmospheric dispersion model for high explosive detonations
Boughton, B.A.; DeLaurentis, J.M.
The Explosive Release Atmospheric Dispersion (ERAD) model is a three-dimensional numerical simulation of turbulent atmospheric transport and diffusion. An integral plume rise technique is used to provide a description of the physical and thermodynamic properties of the cloud of warm gases formed when the explosive detonates. Particle dispersion is treated as a stochastic process which is simulated using a discrete time Lagrangian Monte Carlo method. The stochastic process approach permits a more fundamental treatment of buoyancy effects, calm winds and spatial variations in meteorological conditions. Computational requirements of the three-dimensional simulation are substantially reduced by using a conceptualization in which each Monte Carlo particle represents a small puff that spreads according to a Gaussian law in the horizontal directions. ERAD was evaluated against dosage and deposition measurements obtained during Operation Roller Coaster. The predicted contour areas average within about 50% of the observations. The validation results confirm the model`s representation of the physical processes.
Environmental Conditions Environmental Conditions
Environmental Conditions Environmental Conditions Appendix II The unique geology, hydrology and instream habitat. This chapter examines how environmental conditions in the Deschutes watershed affect, the discussion characterizes the environmental conditions within three watershed areas: the Lower Deschutes
System for time-discretized vacuum ultraviolet spectroscopy of spark breakdown in air
Ryberg, D.; Fierro, A.; Dickens, J.; Neuber, A. [Center for Pulsed Power and Power Electronics, Department of Electrical and Computer Engineering and Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States)
A system for time-discretized spectroscopic measurements of the vacuum ultraviolet (VUV) emission from spark discharges in the 60-160 nm range has been developed for the study of early plasma-forming phenomena. The system induces a spark discharge in an environment close to atmospheric conditions created using a high speed puff value, but is otherwise kept at high vacuum to allow for the propagation of VUV light. Using a vertical slit placed 1.5 mm from the discharge the emission from a small cross section of the discharge is allowed to pass into the selection chamber consisting of a spherical grating, with 1200 grooves/mm, and an exit slit set to 100 ?m. Following the exit slit is a photomultiplier tube with a sodium salicylate scintillator that is used for the time discretized measurement of the VUV signal with a temporal resolution limit of 10 ns. Results from discharges studied in dry air, Nitrogen, SF{sub 6}, and Argon indicate the emission of light with wavelengths shorter than 120 nm where the photon energy begins to approach the regime of direct photoionization.
Constucting Discrete KSurfaces Ivan Sterling
Sterling, Ivan
Constucting Discrete K�Surfaces Ivan Sterling (joint work with Tim Ho#mann, and Ulrich Pinkall) Old it is possible to find other examples (FIGURE 4). 2 #12; Figure 4. Ho#man�Sterling Discrete K�Surface 4. Computer and examples can be found at www.jreality.de. References [1] G.T. Bennett, A new mechanism, Engineering 76
FPGA Acceleration of Discrete Molecular Dynamics Simulation
Herbordt, Martin
' & $ % FPGA Acceleration of Discrete Molecular Dynamics Simulation Joshua Model Thesis submitted UNIVERSITY COLLEGE OF ENGINEERING Thesis FPGA Acceleration of Discrete Molecular Dynamics Simulation Acceleration of Discrete Molecular Dynamics Simulation Joshua Model ABSTRACT Molecular dynamics simulation
Discrete generalized multigroup theory and applications
Zhu, Lei, Ph. D. Massachusetts Institute of Technology
This study develops a fundamentally new discrete generalized multigroup energy expansion theory for the linear Boltzmann transport equation. Discrete orthogonal polynomials are used, in conjunction with the traditional ...
Atmospheric Aerosols Workshop | EMSL
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Atmospheric Aerosols Workshop Atmospheric Aerosols Workshop EMSL Science Theme Advisory Panel Workshop - Atmospheric Aerosol Chemistry, Climate Change, and Air Quality. Baer DR, BJ...
Discrete sine-Gordon dynamics on networks
Dutykh, Denys
In this study we consider the sine-Gordon equation formulated on domains which are not locally homeomorphic to any subset of the Euclidean space. More precisely, we formulate the discrete dynamics on trees and graphs. Each edge is assumed to be a 1D uniform lattice with end points identified with graph vertices. A special treatment is needed at the junctions in order to couple 1D lattices into a global communicating network. Our approach is based on considering the local conservation properties. Some preliminary numerical results are shown on a simple graph containing four loops. These results show the performance of the scheme in non-trivial realistic conditions.
Discrete Structures for Computer Science
Dragan, Feodor F.
-5% Final Exam 40% #12;Why Discrete Math? Design efficient computer systems. �How did Google manage to build issues. #12;16 Sub-Category Graph No Threshold New Science of Networks NYS Electric Power Grid (Thorp
International Symposium on Discrete Mathematics
University, China Ghent University, Belgium CAS-MPG Partner Institute for Computational Biology, ChinaInternational Symposium on Discrete Mathematics and Mathematical Biology August 26�27, 2013 Find Interdisciplinary Centre for Bioinformatics #12;
Atmospheric Aerosol Systems | EMSL
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Science Themes Atmospheric Aerosol Systems Overview Atmospheric Aerosol Systems Biosystem Dynamics & Design Energy Materials & Processes Terrestrial & Subsurface Ecosystems...
Presented by Parallel Discrete Event Simulation
of discrete event execution on high performance computing Business Sensitive � Different optimizations
Tensile damage response from discrete element virtual testing
Paris-Sud XI, Universit� de
Tensile damage response from discrete element virtual testing A. DELAPLACE LMT-Cachan, ENS Cachan conditions on brittle materials, damage can generally not be re- duced to a simple scalar. Microcrack into account the damage anisotropy in phenomenological models is a possible option, but the identification
Final Report for DOE grant DE-FG02-07ER64432 "New Grid and Discretization Technologies for Ocean and Ice Simulations"
Gunzburger, Max
The work reported is in pursuit of these goals: high-quality unstructured, non-uniform Voronoi and Delaunay grids; improved finite element and finite volume discretization schemes; and improved finite element and finite volume discretization schemes. These are sought for application to spherical and three-dimensional applications suitable for ocean, atmosphere, ice-sheet, and other climate modeling applications.
An Efficient Approach for Optical Radiative Transfer Tomography using the Spherical Harmonics Discrete Ordinates Method
Levis, Aviad; Aides, Amit; Davis, Anthony B
This paper introduces a method to preform optical tomography, using 3D radiative transfer as the forward model. We use an iterative approach predicated on the Spherical Harmonics Discrete Ordinates Method (SHDOM) to solve the optimization problem in a scalable manner. We illustrate with an application in remote sensing of a cloudy atmosphere.
Boyer, Edmond
. Polymer-ceramic composites are expected to be the major candidate as dielectric interlayer for embedded of early failures peculiar to ceramic capacitors, technologists are using new polymer-ceramic materials is caused by the mismatch of the thermal expansion coefficient and the thermal conductivity between
? #12;WHAT ISTHE SOLAR ATMOSPHERE? #12;#12;1-D MODEL ATMOSPHERE � Averaged over space and time � GoodINTRODUCTIONTOTHE SOLAR ATMOSPHERE D. Shaun Bloomfield Trinity College Dublin #12;OUTLINE � What is the solar atmosphere? � How is the solar atmosphere observed? � What structures exist and how do they evolve
Software is Discrete Mathematics University of Oklahoma
Page, Rex L.
, discrete mathematics, predicate logic, correctness proofs, formal methods, software engineering. 1Software is Discrete Mathematics Rex L Page University of Oklahoma School of Computer Science Descriptors D.2.4 [Software Engineering]: Software/Program Verification � correctness proofs, formal methods
Discrete and Hybrid Nonholonomy Antonio Bicchi1
Piccoli, Benedetto
Discrete and Hybrid Nonholonomy Antonio Bicchi1 , Alessia Marigo2 , and Benedetto Piccoli3 1 Centro such as cars, trucks with trailers, rolling 3D objects, underactuated mechanisms, satellites, etc., has made of systems, allowing for discrete and hybrid (mixed continuous and discrete) configurations and transi- tions
Numerical Valuation of Discrete Barrier Options with
Chu, Hao-hua
Numerical Valuation of Discrete Barrier Options with the Adaptive Mesh Model and Other Competing for discrete barrier options such that many methods have been suggested and declared to price discrete barrier options fast and accurately but no one can tell exactly that what method is the best. We also make
atmospheric pressure corona: Topics by E-print Network
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atmospheric conditions. Our module is capable of measuring temperature, pressure, wind speed, and particle concentration. The module will take measurements every minute and the...
atmospheric pressure plasmas: Topics by E-print Network
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atmospheric conditions. Our module is capable of measuring temperature, pressure, wind speed, and particle concentration. The module will take measurements every minute and the...
atmospheric pressure measurements: Topics by E-print Network
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atmospheric conditions. Our module is capable of measuring temperature, pressure, wind speed, and particle concentration. The module will take measurements every minute and the...
atmospheric pressure radio: Topics by E-print Network
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atmospheric conditions. Our module is capable of measuring temperature, pressure, wind speed, and particle concentration. The module will take measurements every minute and the...
atmospheric pressure plasma: Topics by E-print Network
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atmospheric conditions. Our module is capable of measuring temperature, pressure, wind speed, and particle concentration. The module will take measurements every minute and the...
atmospheric pressure field: Topics by E-print Network
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atmospheric conditions. Our module is capable of measuring temperature, pressure, wind speed, and particle concentration. The module will take measurements every minute and the...
Discretized configurations and partial partitions
Abrams, Aaron; Hower, Valerie
We show that the discretized configuration space of $k$ points in the $n$-simplex is homotopy equivalent to a wedge of spheres of dimension $n-k+1$. This space is homeomorphic to the order complex of the poset of ordered partial partitions of $\\{1,\\...,n+1\\}$ with exactly $k$ parts. We also compute the Euler characteristic in two different ways, thereby obtaining a topological proof of a combinatorial recurrence satisfied by the Stirling numbers of the second kind.
dimensional discrete Schr�?odinger operator. We prove that if # ess (H) # [-2, 2], then H-H 0 is compact and # ess (H V = 0. One of our main results in this paper is Theorem 1. If # ess (H) # [-2, 2], then V (n) # 0 that # ess (H) = [-2, 2] if and only if V (n) # 0. Our motivation for this result came from two sources
Dispersion Estimates for One-dimensional Discrete Schr�dinger and Wave Equations
Iryna Egorova; Elena Kopylova; Gerald Teschl
We derive dispersion estimates for solutions of the one-dimensional discrete perturbed Schr\\"odinger and wave equations. In particular, we improve upon previous works and weaken the conditions on the potentials. To this end we also provide new results concerning scattering for one-dimensional discrete perturbed Schr\\"odinger operators which are of independent interest. Most notably we show that the reflection and transmission coefficients belong to the Wiener algebra.
Discrete Sets of Singular Cardinality
Fleissner, William G.
singular cardinal k and a closed, cofinal in k, set of cardinals, {kb: � �,. Throughout this paper, Y will be a discrete subset of a space X with | Y \\ = k. We say that t? = (A�)�...
Bell's Jump Process in Discrete Time
Jonathan Barrett; Matthew Leifer; Roderich Tumulka
The jump process introduced by J. S. Bell in 1986, for defining a quantum field theory without observers, presupposes that space is discrete whereas time is continuous. In this letter, our interest is to find an analogous process in discrete time. We argue that a genuine analog does not exist, but provide examples of processes in discrete time that could be used as a replacement.
Atmospheric sampling glow discharge ionization source
McLuckey, S.A.; Glish, G.L.
An atmospheric sampling glow discharge ionization source that can be used in combination with an analytical instrument which operates at high vacuum, such as a mass spectrometer. The atmospheric sampling glow discharge ionization source comprises a chamber with at least one pair of electrodes disposed therein, an inlet for a gaseous sample to be analyzed and an outlet communicating with an analyzer which operates at subatmospheric pressure. The ionization chamber is maintained at a pressure below atmospheric pressure, and a voltage difference is applied across the electrodes to induce a glow discharge between the electrodes, so that molecules passing through the inlet are ionized by the glow discharge and directed into the analyzer. The ionization source accepts the sample under atmospheric pressure conditions and processes it directly into the high vacuum instrument, bridging the pressure gap and drawing off unwanted atmospheric gases. The invention also includes a method for analyzing a gaseous sample using the glow discharge ionization source described above. 3 figs.
Discrete particle transport in porous media : discrete observations of physical mechanisms influencing particle behavior
Yoon, Joon Sik, 1973-
An understanding of how discrete particles in the micron to submicron range behave in porous media is important to a number of environmental problems. Discrete particle behavior in the interior of a porous medium is complex ...
Atmospheric Transport of Radionuclides
Crawford, T.V.
The purpose of atmospheric transport and diffusion calculations is to provide estimates of concentration and surface deposition from routine and accidental releases of pollutants to the atmosphere. This paper discusses this topic.
How atmospheric ice forms | EMSL
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atmospheric ice forms How atmospheric ice forms Released: September 08, 2014 New insights into atmospheric ice formation could improve climate models This study advances our...
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Atmospheric Pressure Reactor System Atmospheric Pressure Reactor System The atmospheric pressure reactor system is designed for testing the efficiency of various catalysts for the...
Climate Sciences: Atmospheric Thermodynamics
Russell, Lynn
1 Climate Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http://aerosol.ucsd.edu/courses.html Text: Curry & Webster Atmospheric Thermodynamics Ch1 Composition Ch2 Laws Ch3 Transfers Ch12 Energy Climate Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http
Verifying Volume Rendering Using Discretization Error Analysis
Kirby, Mike
Verifying Volume Rendering Using Discretization Error Analysis Tiago Etiene, Daniel Jo�nsson, Timo--We propose an approach for verification of volume rendering correctness based on an analysis of the volume rendering integral, the basis of most DVR algorithms. With respect to the most common discretization
Introduction Discrete-time autoregressive process
Di Girolami, Cristina
Introduction Discrete-time autoregressive process Continuous-time Ornstein-Uhlenbeck process Sharp large deviations for the non-stationary Ornstein-Uhlenbeck process Bernard Bercu Bordeaux University-Uhlenbeck process 1 / 46 #12;Introduction Discrete-time autoregressive process Continuous-time Ornstein
Terrestrial Planet Atmospheres. The Moon's Sodium Atmosphere
Walter, Frederick M.
;Origins of Atmospheres � Outgassing � Volcanoes expel water, CO2, N2, H2S, SO2 removed by the Fme convecFon reaches deserts #12;Water and Ice Clouds #12;H2SO4
Discrete analysis of stochastic NMR
Wong, Sam Tak-Sum
Stochastic NMR is an efficient technique for high field in vivo imaging and spectroscopic studies in cases where the peak rf power required may be prohibitively high for conventional pulsed NMR techniques. This dissertation presents a theoretical analysis of a stochastic NMR method of acquiring spectroscopy data. The spin system is excited with rf pulses where the flip angles or the phases of the pulses are samples of a discrete stochastic process. The method is formulated as a stochastic difference equation which is then converted to ordinary deterministic difference equations describing the input-output cross-correlation, average signal power and signal power spectrum. The solutions of these equations are used to evaluate the stochastic, technique in terms of peak rf power requirement, spectral distortions and signal-to-noise ratio. Experimental results are also presented which verify the results of the discrete analysis. The analysis shows that the maximum signal-to-noise ratio is achieved when the RMS flip angle is approximately the Ernst angle. When the RMS flip angle is below the Ernst angle, the input-output cross-correlation is a good estimate of the FID. Increase of excitation power causes line broadening. In addition, the use of random flip angle, fixed phase excitation causes a notch artifact and non-uniform response across the spectrum both of which are not found in two new types of excitation, the random phase excitation and the random quadrature excitation. The signal power spectrum is also a good estimate of the real spectrum. The approximation of the cross-correlation by a time average causes systematic noise. The amount of systematic noise is found to be significantly reduced when an entire maximum length sequence (MLS) is used for excitation. Noise-like distortion at high power MLS excitation is discovered to be related to the number of feedback paths in the MLS generator. 29 refs., 58 figs.
Identification and Estimation of a Discrete Game of Complete Information
Bajari, Patrick
We discuss the identification and estimation of discrete games of complete information. Following Bresnahan and Reiss (1990, 1991), a discrete game is a generalization of a standard discrete choice model where utility ...
Resonance and web structure in discrete soliton systems: the two-dimensional Toda lattice and its fully discrete and ultra-discrete versions
Ken-ichi Maruno; Gino Biondini
We present a class of solutions of the two-dimensional Toda lattice equation, its fully discrete analogue and its ultra-discrete limit. These solutions demonstrate the existence of soliton resonance and web-like structure in discrete integrable systems such as differential-difference equations, difference equations and cellular automata (ultra-discrete equations).
Discrete Symmetry and Stability in Hamiltonian Dynamics
Tassos Bountis; George Chechin; Vladimir Sakhnenko
In this tutorial we address the existence and stability of periodic and quasiperiodic orbits in N degree of freedom Hamiltonian systems and their connection with discrete symmetries. Of primary importance in our study are the nonlinear normal modes (NNMs), i.e periodic solutions which represent continuations of the system's linear normal modes in the nonlinear regime. We examine the existence of such solutions and discuss different methods for constructing them and studying their stability under fixed and periodic boundary conditions. In the periodic case, we employ group theoretical concepts to identify a special type of NNMs called one-dimensional "bushes". We describe how to use linear combinations such NNMs to construct s(>1)-dimensional bushes of quasiperiodic orbits, for a wide variety of Hamiltonian systems and exploit the symmetries of the linearized equations to simplify the study of their destabilization. Applying this theory to the Fermi Pasta Ulam (FPU) chain, we review a number of interesting results, which have appeared in the recent literature. We then turn to an analytical and numerical construction of quasiperiodic orbits, which does not depend on the symmetries or boundary conditions. We demonstrate that the well-known "paradox" of FPU recurrences may be explained in terms of the exponential localization of the energies Eq of NNM's excited at the low part of the frequency spectrum, i.e. q=1,2,3,.... Thus, we show that the stability of these low-dimensional manifolds called q-tori is related to the persistence or FPU recurrences at low energies. Finally, we discuss a novel approach to the stability of orbits of conservative systems, the GALIk, k=2,...,2N, by means of which one can determine accurately and efficiently the destabilization of q-tori, leading to the breakdown of recurrences and the equipartition of energy, at high values of the total energy E.
Harmonic pinnacles in the Discrete Gaussian model
Eyal Lubetzky; Fabio Martinelli; Allan Sly
The 2D Discrete Gaussian model gives each height function $\\eta : \\mathbb{Z}^2\\to\\mathbb{Z}$ a probability proportional to $\\exp(-\\beta \\mathcal{H}(\\eta))$, where $\\beta$ is the inverse-temperature and $\\mathcal{H}(\\eta) = \\sum_{x\\sim y}(\\eta_x-\\eta_y)^2$ sums over nearest-neighbor bonds. We consider the model at large fixed $\\beta$, where it is flat unlike its continuous analog (the Gaussian Free Field). We first establish that the maximum height in an $L\\times L$ box with 0 boundary conditions concentrates on two integers $M,M+1$ with $M\\sim \\sqrt{(1/2\\pi\\beta)\\log L\\log\\log L}$. The key is a large deviation estimate for the height at the origin in $\\mathbb{Z}^2$, dominated by "harmonic pinnacles", integer approximations of a harmonic variational problem. Second, in this model conditioned on $\\eta\\geq 0$ (a floor), the average height rises, and in fact the height of almost all sites concentrates on levels $H,H+1$ where $H\\sim M/\\sqrt{2}$. This in particular pins down the asymptotics, and corrects the order, in results of Bricmont, El-Mellouki and Fr\\"ohlich (1986), where it was argued that the maximum and the height of the surface above a floor are both of order $\\sqrt{\\log L}$. Finally, our methods extend to other classical surface models (e.g., restricted SOS), featuring connections to $p$-harmonic analysis and alternating sign matrices.
Discrete Fourier-based Correlations for Entanglement Detection
Ryo Namiki; Yuuki Tokunaga
We introduce two forms of correlations on two $d$-level (qudit) systems for entanglement detection. The correlations can be measured via experimentally tractable two local measurement settings and their separable bounds are determined by discrete Fourier-based uncertainty relations. They are useful to estimate lower bounds of the Schmidt number in order to clarify generation of a genuine qudit entanglement. We also present inseparable conditions for multi-qudit systems associated with the qudit stabilizer formalism as another role of the correlations on the inseparability problem.
Heterogeneous Surface-Based Freezing of Atmospheric Aerosols Containing Ash, Soot, and Soil
Fornea, Adam P.
Nucleation of ice crystals in the atmosphere often occurs through heterogeneous freezing processes facilitated by an atmospheric aerosol that acts as the ice nuclei (IN). Depending on ambient conditions and aerosol composition, heterogeneous...
EMSL - Atmospheric Aerosol Systems
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scienceatmospheric The Atmospheric Aerosol Systems Science Theme focuses on understanding the chemistry, physics and molecular-scale dynamics of aerosols for model...
Thomas K. Gaisser
Starting with an historical review, I summarize the status of calculations of the flux of atmospheric neutrinos and how they compare to measurements.
Spatially Discrete FitzHugh-Nagumo Equations
Elmer, Christopher E.; Van Vleck, Erik
We consider pulse and front solutions to a spatially discrete FitzHugh--Nagumo equation that contains terms to represent both depolarization and hyperpolarization of the nerve axon. We demonstrate a technique for deriving ...
Xiaoning Wu
In this paper, we consider the discrete AKNS-D hierarchy, find the construction of the hierarchy, prove the bilinear identity and give the construction of the $\\tau$-functions of this hierarchy.
Atmospheric Dynamics II Instructor
AT602 Atmospheric Dynamics II 2 credits Instructor: David W. J. Thompson davet: An Introduction to Dynamic Meteorology, 5th Edition, Academic Press (recommended) · Marshall, J., and Plumb, R. A., 2008: Atmosphere, Ocean, and Climate Dynamics: An Introductory Text, Academic Press. · Vallis, G. K
Atmospheric Thermodynamics Composition
Russell, Lynn
1 Atmospheric Thermodynamics Ch1 Composition Ch2 Laws Ch3 Transfers Ch12 EnergyBalance Ch4 Water Ch Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http #12;2 Review from Ch. 1 � Thermodynamic quantities � Composition � Pressure � Density � Temperature
Green's function of a finite chain and the discrete Fourier transform
S. Cojocaru
A new expression for the Green's function of a finite one-dimensional lattice with nearest neighbor interaction is derived via discrete Fourier transform. Solution of the Heisenberg spin chain with periodic and open boundary conditions is considered as an example. Comparison to Bethe ansatz clarifies the relation between the two approaches.
Irreducibility and co-primeness as an integrability criterion for discrete equations
Masataka Kanki; Jun Mada; Takafumi Mase; Tetsuji Tokihiro
We study the Laurent property, the irreducibility and co-primeness of discrete integrable and non-integrable equations. First we study a discrete integrable equation related to the Somos-4 sequence, and also a non-integrable equation as a comparison. We prove that the conditions of irreducibility and co-primeness hold only in the integrable case. Next, we generalize our previous results on the singularities of the discrete Korteweg-de Vries (dKdV) equation. In our previous paper (arXiv:1311.0060), we described the singularity confinement test (one of the integrability criteria) using the Laurent property, and the irreducibility, and co-primeness of the terms in the bilinear dKdV equation, in which we only considered simplified boundary conditions. This restriction was needed to obtain simple (monomial) relations between the bilinear form and the nonlinear form of the dKdV equation. In this paper, we prove the co-primeness of the terms in the nonlinear dKdV equation for general initial conditions and boundary conditions, by using the localization of Laurent rings and the interchange of the axes. We assert that co-primeness of the terms can be used as a new integrability criterion, which is a mathematical re-interpretation of the confinement of singularities in the case of discrete equations. v2, v3: minor revisions
Eindhoven, Technische Universiteit
. The continuity condition t() + � (q) = 0 combined with Darcy law (1.1) leads to Richards' equation (1.2) tERROR ESTIMATES FOR A TIME DISCRETIZATION METHOD FOR THE RICHARDS' EQUATION IULIU SORIN POP' equation. Written in its saturation-based form, this nonlinear para- bolic equation models water flow
Mortar finite element discretization of a model coupling Darcy and Stokes equations
Boyer, Edmond
Mortar finite element discretization of a model coupling Darcy and Stokes equations by C. Bernardi1 flowing on a homogeneous porous ground, we consider a system where the Darcy and Stokes equations�erons un syst`eme o`u les �equations de Darcy et de Stokes sont coupl�ees par des conditions de raccord
Energy Levels of "Hydrogen Atom" in Discrete Time Dynamics
Andrei Khrennikov; Yaroslav Volovich
We analyze dynamical consequences of a conjecture that there exists a fundamental (indivisible) quant of time. In particular we study the problem of discrete energy levels of hydrogen atom. We are able to reconstruct potential which in discrete time formalism leads to energy levels of unperturbed hydrogen atom. We also consider linear energy levels of quantum harmonic oscillator and show how they are produced in the discrete time formalism. More generally, we show that in discrete time formalism finite motion in central potential leads to discrete energy spectrum, the property which is common for quantum mechanical theory. Thus deterministic (but discrete time!) dynamics is compatible with discrete energy levels.
atmospheric aerosol limb: Topics by E-print Network
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coefficient is 0.5 and then 1.0 2. For the same conditions calculate the H Weber, Rodney 5 Secondary organic aerosol 1. Atmospheric chemical mechanism for production...
atmospheric aerosol desarrollo: Topics by E-print Network
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coefficient is 0.5 and then 1.0 2. For the same conditions calculate the H Weber, Rodney 4 Secondary organic aerosol 1. Atmospheric chemical mechanism for production...
atmospheric aerosols recorded: Topics by E-print Network
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coefficient is 0.5 and then 1.0 2. For the same conditions calculate the H Weber, Rodney 4 Secondary organic aerosol 1. Atmospheric chemical mechanism for production...
atmospheric aerosols relation: Topics by E-print Network
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coefficient is 0.5 and then 1.0 2. For the same conditions calculate the H Weber, Rodney 4 Secondary organic aerosol 1. Atmospheric chemical mechanism for production...
atmospheric pressure radio-frequency: Topics by E-print Network
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atmospheric conditions. Our module is capable of measuring temperature, pressure, wind speed, and particle concentration. The module will take measurements every minute and...
Modelling and numerical approximation of a 2.5D set of equations for mesoscale atmospheric processes
Kalise, Dante
The set of 3D inviscid primitive equations for the atmosphere is dimensionally reduced by a Discontinuous Galerkin discretization in one horizontal direction. The resulting model is a 2D system of balance laws where with a source term depending on the layering procedure and the choice of coupling fluxes, which is established in terms of upwind considerations. The "2.5D" system is discretized via a WENO-TVD scheme based in a flux limiter centered approach. We study four tests cases related to atmospheric phenomena to analyze the physical validity of the model.
Atmospheric Science: An introductory survey 1. Introduction to the atmosphere
Folkins, Ian
Sound Convergence Zone #12;Terrain effects #12;Von Karman vortex streets #12;Atmosphere in Earth system
Simulated Arctic atmospheric feedbacks associated with late summer sea ice anomalies
Moore, John
Simulated Arctic atmospheric feedbacks associated with late summer sea ice anomalies A. Rinke,1,2 K depend on regional and decadal variations in the coupled atmosphere-ocean-sea ice system. Citation: Rinke to investigate feedbacks between September sea ice anomalies in the Arctic and atmospheric conditions in autumn
An energy absorbing far-field boundary condition for the elastic wave equation
Petersson, N A; Sjogreen, B
The authors present an energy absorbing non-reflecting boundary condition of Clayton-Engquist type for the elastic wave equation together with a discretization which is stable for any ratio of compressional to shear wave speed. They prove stability for a second order accurate finite-difference discretization of the elastic wave equation in three space dimensions together with a discretization of the proposed non-reflecting boundary condition. The stability proof is based on a discrete energy estimate and is valid for heterogeneous materials. The proof includes all six boundaries of the computational domain where special discretizations are needed at the edges and corners. The stability proof holds also when a free surface boundary condition is imposed on some sides of the computational domain.
Effects of Changing Atmospheric Conditions on Wind Turbine Performance (Poster)
Clifton, A.
Multi-megawatt, utility-scale wind turbines operate in turbulent and dynamic winds that impact turbine performance in ways that are gradually becoming better understood. This poster presents a study made using a turbulent flow field simulator (TurbSim) and a Turbine aeroelastic simulator (FAST) of the response of a generic 1.5 MW wind turbine to changing inflow. The turbine power output is found to be most sensitive to wind speed and turbulence intensity, but the relationship depends on the wind speed with respect to the turbine's rated wind speed. Shear is found to be poorly correlated to power. A machine learning method called 'regression trees' is used to create a simple model of turbine performance that could be used as part of the wind resource assessment process. This study has used simple flow fields and should be extended to more complex flows, and validated with field observations.
Fast mix table construction for material discretization
Johnson, S. R. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)
An effective hybrid Monte Carlo-deterministic implementation typically requires the approximation of a continuous geometry description with a discretized piecewise-constant material field. The inherent geometry discretization error can be reduced somewhat by using material mixing, where multiple materials inside a discrete mesh voxel are homogenized. Material mixing requires the construction of a 'mix table,' which stores the volume fractions in every mixture so that multiple voxels with similar compositions can reference the same mixture. Mix table construction is a potentially expensive serial operation for large problems with many materials and voxels. We formulate an efficient algorithm to construct a sparse mix table in O(number of voxels x log number of mixtures) time. The new algorithm is implemented in ADVANTG and used to discretize continuous geometries onto a structured Cartesian grid. When applied to an end-of-life MCNP model of the High Flux Isotope Reactor with 270 distinct materials, the new method improves the material mixing time by a factor of 100 compared to a naive mix table implementation. (authors)
Regularized Discrete Optimal Transport Sira Ferradans1
Boyer, Edmond
. firstname.lastname@example.com Abstract. This article introduces a generalization of discrete in modified images. In this article, we propose a variational formalism to relax and regularize the transport dedicated linear solvers (transportation simplex) and combinatorial algorithms (such as the Hungarian
All-optical discrete vortex switch
Desyatnikov, Anton S. [Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia); Dennis, Mark R. [H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Ferrando, Albert [Interdisciplinary Modeling Group, InterTech and Departament d'Optica, Universitat de Valencia, E-46100 Burjassot (Spain)
We introduce discrete vortex solitons and vortex breathers in circular arrays of nonlinear waveguides. The simplest vortex breather in a four-waveguide coupler is a nonlinear dynamic state changing its topological charge between +1 and -1 periodically during propagation. We find the stability domain for this solution and suggest an all-optical vortex switching scheme.
Dynamic Discrete Power Control in Cellular Networks
Avrachenkov, Konstantin
1 Dynamic Discrete Power Control in Cellular Networks Eitan Altman, Konstantin Avrachenkov, Ishai. In each of the two frameworks, we consider both cooperative as well as non-cooperative power control. We utilization. It is, therefore, in the interests of the users to control their transmit powers levels so
Model Uncertainty in Discrete Event Stanley Young
Garg, Vijay
Abstract Earlier work concerning control of discrete event systems usually assumed that a correct model to test for the correct model or noti cation that the remaining models cannot be controllably distin- guished. We use the nite state machine model with controllable and uncontrollable events presented
Contributions to the development of residual discretizations
Paris-Sud XI, Universit� de
Contributions to the development of residual discretizations for hyperbolic conservation laws with application to shallow water flows Manuscript submitted in fulfillment of the requirements for the obtention;Contents 1 Overview 9 1.1 Residual schemes for hyperbolic conservation laws
Discrete profile alignment via constrained information bottleneck
Chechik, Gal
Discrete profile alignment via constrained information bottleneck Sean O'Rourke firstname.lastname@example.com Abstract Amino acid profiles, which capture position-specific mutation prob- abilities, are a richer encoding of biological sequences than the in- dividual sequences themselves. However, profile comparisons
Discrete profile alignment via constrained information bottleneck
Chechik, Gal
Discrete profile alignment via constrained information bottleneck Sean O'Rourke # email@example.com Abstract Amino acid profiles, which capture positionspecific mutation prob abilities, are a richer encoding of biological sequences than the in dividual sequences themselves. However, profile comparisons
Comment on ``Discrete Boltzmann Equation for Microfluidics''
Luo, Li-Shi
Comment on ``Discrete Boltzmann Equation for Microfluidics'' In a recent Letter [1], Li and Kwok use a lattice Boltzmann equation (LBE) for microfluidics. Their main claim is that an LBE model for microfluidics can be constructed based on the ``Bhatnagar-Gross-Kooky [sic]'' model by including ``the
Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]
This Notice ensures that DOE uniformly meets the requirements of the Homeland Security Advisory System outlined in Homeland Security Presidential Directive-3, Threat Conditions and Associated Protective Measures, dated 3-11-02, and provides responses specified in Presidential Decision Directive 39, U.S. Policy on Counterterrorism (U), dated 6-21-95. It cancels DOE N 473.8, Security Conditions, dated 8-7-02. Extended until 7-7-06 by DOE N 251.64, dated 7-7-05 Cancels DOE N 473.8
Controller Synthesis of Discrete Linear Plants Using MATTEO SLANINA
Sankaranarayanan, Sriram
Controller Synthesis of Discrete Linear Plants Using Polyhedra MATTEO SLANINA Stanford University controllers for linear discrete systems with disturbances. Given a plant description and a safety We study techniques for synthesizing synchronous controllers for affine plants with disturbances
Discretization and Algorithms for Strong Coupling in Computational Aeroelasticity
8 4.1 Flow discretization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2 Structural discretization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.3 Mimicing the energy.4 A bifurcation at M1 = 0:95 . . . . . . . . . . . . . . . . . . . . . . . . . . 22 6.5 Stability chart
Defining Employee Perceptions of Discretion: When, Where, and How
Thompson, Rebecca Jean
discretion: choice over when, where, and how one works. Second, the influence of these three forms of discretion on both work-related outcomes (job satisfaction, burnout, and turnover intentions) and nonwork-related outcomes (life satisfaction, work...
Math 209 Discrete Mathematics Spring 2008 Instructor Amites Sarkar
Sarkar, Amites
Math 209 Discrete Mathematics Spring 2008 Instructor Amites Sarkar Text Discrete Mathematics, Tuesdays, Thursdays and Fridays, in 216 Bond Hall. My phone number is 650 7569 and my e-mail is amites.sarkar
Math 209 Discrete Mathematics Spring 2011 Instructor Dr. Amites Sarkar
Sarkar, Amites
Math 209 Discrete Mathematics Spring 2011 Instructor Dr. Amites Sarkar Text Discrete Mathematics, in 216 Bond Hall. My phone number is 650 7569 and my e-mail is email@example.com #12;
Math 209 Discrete Mathematics Winter 2009 Instructor Amites Sarkar
Sarkar, Amites
Math 209 Discrete Mathematics Winter 2009 Instructor Amites Sarkar Text Discrete Mathematics, Tuesdays, Thursdays and Fridays, in 216 Bond Hall. My phone number is 650 7569 and my e-mail is amites.sarkar
Discrete Spectral Transformations of Skew Orthogonal Polynomials and Associated Discrete Integrable Systems
Hiroshi Miki; Hiroaki Goda; Satoshi Tsujimoto
Discrete spectral transformations of skew orthogonal polynomials are presented. From these spectral transformations, it is shown that the corresponding discrete integrable systems are derived both in 1+1 dimension and in 2+1 dimension. Especially in the (2+1)-dimensional case, the corresponding system can be extended to 2x2 matrix form. The factorization theorem of the Christoffel kernel for skew orthogonal polynomials in random matrix theory is presented as a by-product of these transformations.
Discrete spectral transformations of skew orthogonal polynomials and associated discrete integral systems
Miki, Hiroshi; Tsujimoto, Satoshi
Discrete spectral transformations of skew orthognal polynomials are presented. From these spectral transformations, it is shown that the corresponding discrete integrable systems are derived both in 1+1 dimension and in 2+1 dimension. Especially in the 2+1 dimensional case, the corresponding system can be extended to 2x2 matrix form. The factorization theorem of the skew-Christoffel kernel in random matrix theory is presented as a by-product of these transformations.
Optimal control, nonlinear systems, state constraints, Euler discretization, rate of ... convergence, provided with modern variational techniques, are also [25];�...
Heng, Kevin [ETH Zuerich, Institute for Astronomy, Wolfgang-Pauli-Strasse 27, CH-8093, Zuerich (Switzerland); Kopparla, Pushkar [ETH Zuerich, Institute for Atmospheric and Climate Science, Universitaetstrasse 16, CH-8092, Zuerich (Switzerland)
We investigate the stability of super-Earth atmospheres around M stars using a seven-parameter, analytical framework. We construct stability diagrams in the parameter space of exoplanetary radius versus semimajor axis and elucidate the regions in which the atmospheres are stable against the condensation of their major constituents, out of the gas phase, on their permanent nightside hemispheres. We find that super-Earth atmospheres that are nitrogen-dominated (Earth-like) occupy a smaller region of allowed parameter space, compared to hydrogen-dominated atmospheres, because of the dual effects of diminished advection and enhanced radiative cooling. Furthermore, some super-Earths which reside within the habitable zones of M stars may not possess stable atmospheres, depending on the mean molecular weight and infrared photospheric pressure of their atmospheres. We apply our stability diagrams to GJ 436b and GJ 1214b, and demonstrate that atmospheric compositions with high mean molecular weights are disfavored if these exoplanets possess solid surfaces and shallow atmospheres. Finally, we construct stability diagrams tailored to the Kepler data set, for G and K stars, and predict that about half of the exoplanet candidates are expected to harbor stable atmospheres if Earth-like conditions are assumed. We include 55 Cancri e and CoRoT-7b in our stability diagram for G stars.
Read, Peter L.
transfer Solar heating of surface, and atmosphere via dust absorption Infrared CO2 band cooling (especially around 667 cm-1) nonLTE near-infrared heating of CO2 and nonLTE cooling effects above ~60-80 km. Baroclinic waves, scales, heat and momentum transport, seasonal occurrence. Qualitative treatment
Laboratory for Atmospheric and
Mojzsis, Stephen J.
. Along with this growth came a new building on campus and a new name: the Laboratory for Atmospheric of the Sun to the outermost fringes of the solar system. With LASP's continuing operations role in the planet traditional and stable approach based on federal agency funding of research grant
Condition assessment of nonlinear processes
Hively, Lee M. (Philadelphia, TN); Gailey, Paul C. (Athens, OH); Protopopescu, Vladimir A. (Knoxville, TN)
There is presented a reliable technique for measuring condition change in nonlinear data such as brain waves. The nonlinear data is filtered and discretized into windowed data sets. The system dynamics within each data set is represented by a sequence of connected phase-space points, and for each data set a distribution function is derived. New metrics are introduced that evaluate the distance between distribution functions. The metrics are properly renormalized to provide robust and sensitive relative measures of condition change. As an example, these measures can be used on EEG data, to provide timely discrimination between normal, preseizure, seizure, and post-seizure states in epileptic patients. Apparatus utilizing hardware or software to perform the method and provide an indicative output is also disclosed.
SIO 217a Atmospheric and Climate Sciences I: Atmospheric Thermodynamics
Russell, Lynn
SIO 217a Atmospheric and Climate Sciences I: Atmospheric Thermodynamics Course Syllabus and Lecture Schedule Instructor: Lynn Russell, 343 NH, 534-4852, email@example.com Text: Thermodynamics of Atmospheres of Thermodynamics (Work, Heat, First Law, Second Law, Heat Capacity, Adiabatic Processes) 5-Oct F Hurricane Example
Degeneracy and Discreteness in Cosmological Model Fitting
Teng, Huan-Yu; Hu, Huan-Chen; Zhang, Tong-Jie
We explore the degeneracy and discreteness problems in the standard cosmological model ({\\Lambda}CDM). We use the Observational Hubble Data (OHD) and the type Ia supernova (SNe Ia) data to study this issue. In order to describe the discreteness in fitting of data, we define a factor G to test the influence from each single data point and analyze the goodness of G. Our results indicate that a higher absolute value of G shows a better capability of distinguishing models, which means the parameters are restricted into smaller confidence intervals with a larger figure of merit evaluation. Consequently, we claim that the factor G is an effective way in model differentiation when using different models to fit the observational data.
A combinatorial approach to discrete geometry
L. Bombelli; M. Lorente
We present a paralell approach to discrete geometry: the first one introduces Voronoi cell complexes from statistical tessellations in order to know the mean scalar curvature in term of the mean number of edges of a cell. The second one gives the restriction of a graph from a regular tessellation in order to calculate the curvature from pure combinatorial properties of the graph. Our proposal is based in some epistemological pressupositions: the macroscopic continuous geometry is only a fiction, very usefull for describing phenomena at certain sacales, but it is only an approximation to the true geometry. In the discrete geometry one starts from a set of elements and the relation among them without presuposing space and time as a background.
Properties of Ellipticity Correlation with Atmospheric Structure From Gemini South
Asztalos, Stephen J.; /LLNL, Livermore; de Vries, W.H.; /UC, Davis /LLNL, Livermore; Rosenberg, L.J; Treadway, T.; /LLNL, Livermore; Burke, D.; /SLAC; Claver, C.; Saha, A.; /NOAO, Tucson; Puxley, P.; /Gemini Observ., La Serena
Cosmic shear holds great promise for a precision independent measurement of {Omega}{sub m}, the mass density of the universe relative to the critical density. The signal is expected to be weak, so a thorough understanding of systematic effects is crucial. An important systematic effect is the atmosphere: shear power introduced by the atmosphere is larger than the expected signal. Algorithms exist to extract the cosmic shear from the atmospheric component, though a measure of their success applied to a range of seeing conditions is lacking. To gain insight into atmospheric shear, Gemini South imaging in conjunction with ground condition and satellite wind data were obtained. We find that under good seeing conditions Point-Spread-Function (PSF) correlations persist well beyond the separation typical of high-latitude stars. Under these conditions, ellipticity residuals based on a simple PSF interpolation can be reduced to within a factor of a few of the shot-noise induced ellipticity floor. We also find that the ellipticity residuals are highly correlated with wind direction. Finally, we correct stellar shapes using a more sophisticated procedure and generate shear statistics from stars. Under all seeing conditions in our data set the residual correlations lie everywhere below the target signal level. For good seeing we find that the systematic error attributable to atmospheric turbulence is comparable in magnitude to the statistical error (shape noise) over angular scales relevant to present lensing surveys.
Pluto's Atmosphere Does Not Collapse
Olkin, C B; Borncamp, D; Pickles, A; Sicardy, B; Assafin, M; Bianco, F B; Buie, M W; de Oliveira, A Dias; Gillon, M; French, R G; Gomes, A Ramos; Jehin, E; Morales, N; Opitom, C; Ortiz, J L; Maury, A; Norbury, M; Ribas, F B; Smith, R; Wasserman, L H; Young, E F; Zacharias, M; Zacharias, N
Combining stellar occultation observations probing Pluto's atmosphere from 1988 to 2013 and models of energy balance between Pluto's surface and atmosphere, we conclude that Pluto's atmosphere does not collapse at any point in its 248-year orbit. The occultation results show an increasing atmospheric pressure with time in the current epoch, a trend present only in models with a high thermal inertia and a permanent N2 ice cap at Pluto's north rotational pole.
${\\mathbb{Z}}_N$ graded discrete Lax pairs and discrete integrable systems
Allan P. Fordy; Pavlos Xenitidis
We introduce a class of ${\\mathbb{Z}}_N$ graded discrete Lax pairs, with $N\\times N$ matrices, linear in the spectral parameter. We give a classification scheme for such Lax pairs and the associated discrete integrable systems. We present two potential forms and completely classify the generic case. Many well known examples belong to our scheme for $N=2$, so many of our systems may be regarded as generalisations of these. Even at $N=3$, several new integrable systems arise. Many of our equations are mutually compatible, so can be used together to form "coloured" lattices. We also present continuous isospectral deformations of our Lax pairs, giving compatible differential-difference systems, which play the role of continuous symmetries of our discrete systems. We present master symmetries and a recursive formulae for their respective hierarchies, for the generic case. We present two nonlocal symmetries of our discrete systems, which have a natural representation in terms of the potential forms. These give rise to the two-dimensional Toda lattice, with our nonlinear symmetries being the B\\"acklund transformations and our discrete system being the nonlinear superposition formula (for the generic case).
Differential atmospheric tritium sampler
Griesbach, O.A.; Stencel, J.R.
An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The moisture then passes through a combustion chamber where hydrogen gas in the form of H/sub 2/ or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.
Differential atmospheric tritium sampler
Griesbach, Otto A. (Langhorne, PA); Stencel, Joseph R. (Skillman, NJ)
An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The mixture then passes through a combustion chamber where hydrogen gas in the form of H.sub.2 or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.
Discrete ordinates transport methods for problems with highly forward-peaked scattering
Pautz, S.D.
The author examines the solutions of the discrete ordinates (S{sub N}) method for problems with highly forward-peaked scattering kernels. He derives conditions necessary to obtain reasonable solutions in a certain forward-peaked limit, the Fokker-Planck (FP) limit. He also analyzes the acceleration of the iterative solution of such problems and offer improvements to it. He extends the analytic Fokker-Planck limit analysis to the S{sub N} equations. This analysis shows that in this asymptotic limit the S{sub N} solution satisfies a pseudospectral discretization of the FP equation, provided that the scattering term is handled in a certain way (which he describes) and that the analytic transport solution satisfies an analytic FP equation. Similar analyses of various spatially discretized S{sub N} equations reveal that they too produce solutions that satisfy discrete FP equations, given the same provisions. Numerical results agree with these theoretical predictions. He defines a multidimensional angular multigrid (ANMG) method to accelerate the iterative solution of highly forward-peaked problems. The analyses show that a straightforward application of this scheme is subject to high-frequency instabilities. However, by applying a diffusive filter to the ANMG corrections he is able to stabilize this method. Fourier analyses of model problems show that the resulting method is effective at accelerating the convergence rate when the scattering is forward-peaked. The numerical results demonstrate that these analyses are good predictors of the actual performance of the ANMG method.
Novel coupling scheme to control dynamics of coupled discrete systems
Snehal M. Shekatkar; G. Ambika
We present a new coupling scheme to control spatio-temporal patterns and chimeras on 1-d and 2-d lattices and random networks of discrete dynamical systems. The scheme involves coupling with an external lattice or network of damped systems. When the system network and external network are set in a feedback loop, the system network can be controlled to a homogeneous steady state or synchronized periodic state with suppression of the chaotic dynamics of the individual units. The control scheme has the advantage that its design does not require any prior information about the system dynamics or its parameters and works effectively for a range of parameters of the control network. We analyze the stability of the controlled steady state or amplitude death state of lattices using the theory of circulant matrices and Routh-Hurwitz's criterion for discrete systems and this helps to isolate regions of effective control in the relevant parameter planes. The conditions thus obtained are found to agree well with those obtained from direct numerical simulations in the specific context of lattices with logistic map and Henon map as on-site system dynamics. We show how chimera states developed in an experimentally realizable 2-d lattice can be controlled using this scheme. We propose this mechanism can provide a phenomenological model for the control of spatio-temporal patterns in coupled neurons due to non-synaptic coupling with the extra cellular medium. We extend the control scheme to regulate dynamics on random networks and adapt the master stability function method to analyze the stability of the controlled state for various topologies and coupling strengths.
A Model of Intra-seasonal Oscillations in the Earth atmosphere
Elena Kartashova; Victor S. L'vov
We suggest a way of rationalizing an intra-seasonal oscillations (IOs) of the Earth atmospheric flow as four meteorological relevant triads of interacting planetary waves, isolated from the system of all the rest planetary waves. Our model is independent of the topography (mountains, etc.) and gives a natural explanation of IOs both in the North and South Hemispheres. Spherical planetary waves are an example of a wave mesoscopic system obeying discrete resonances that also appears in other areas of physics.
Bilinear control of discrete spectrum Schr�dinger operators
Kais Ammari; Zied Ammari
The bilinear control problem of the Schr\\"odinger equation $i\\frac{\\partial}{\\partial t}\\psi(t)$ $=(A+u(t) B)\\psi(t)$, where $u(t)$ is the control function, is investigated through topological irreducibility of the set $\\mathfrak{M}=\\{e^{-it (A+u B)}, u\\in \\mathbb{R}, t>0\\}$ of bounded operators. This allows to prove the approximate controllability of such systems when the uncontrolled Hamiltonian $A$ has a simple discrete spectrum and under an appropriate assumption on $B$.
Quantumness of discrete Hamiltonian cellular automata
Hans-Thomas Elze
We summarize a recent study of discrete (integer-valued) Hamiltonian cellular automata (CA) showing that their dynamics can only be consistently defined, if it is linear in the same sense as unitary evolution described by the Schr\\"odinger equation. This allows to construct an invertible map between such CA and continuous quantum mechanical models, which incorporate a fundamental scale. Presently, we emphasize general aspects of these findings, the construction of admissible CA observables, and the existence of solutions of the modified dispersion relation for stationary states.
Compartmentalization analysis using discrete fracture network models
La Pointe, P.R.; Eiben, T.; Dershowitz, W. [Golder Associates, Redmond, VA (United States); Wadleigh, E. [Marathon Oil Co., Midland, TX (United States)
This paper illustrates how Discrete Fracture Network (DFN) technology can serve as a basis for the calculation of reservoir engineering parameters for the development of fractured reservoirs. It describes the development of quantitative techniques for defining the geometry and volume of structurally controlled compartments. These techniques are based on a combination of stochastic geometry, computational geometry, and graph the theory. The parameters addressed are compartment size, matrix block size and tributary drainage volume. The concept of DFN models is explained and methodologies to compute these parameters are demonstrated.
Unitary Evolution on a Discrete Phase Space
E. G. Floratos; S. Nicolis
We construct unitary evolution operators on a phase space with power of two discretization. These operators realize the metaplectic representation of the modular group SL(2,Z_{2^n}). It acts in a natural way on the coordinates of the non-commutative 2-torus, T_{2^n}^2$ and thus is relevant for non-commutative field theories as well as theories of quantum space-time. The class of operators may also be useful for the efficient realization of new quantum algorithms.
Modified discrete random walk with absorption
Theo van Uem
We obtain expected number of arrivals, probability of arrival, absorption probabilities and expected time before absorption for a modified discrete random walk on the (sub)set of integers. In a [pqrs] random walk the particle can move one step forward or backward, stay for a moment in the same state or it can be absorbed immediately in the current state. M[pqrs] is a modified version, where probabilities on both sides of a multiple function barrier M are of different [pqrs] type.
SNAP:SN (Discrete Ordinates) Application Proxy
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atmospheres thin atmospheres: Topics by E-print Network
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to optical depth perturbations. In Earth-type atmospheres sustained planetary greenhouse effect with a stable ground surface temperature can only exist at a particular...
attila discrete ordinance: Topics by E-print Network
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recurrence satisfied by the Stirling numbers of the second kind. Abrams, Aaron; Hower, Valerie 2010-01-01 428 VARIATIONAL ESTIMATES FOR DISCRETE SCHR Mathematics Websites...
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recurrence satisfied by the Stirling numbers of the second kind. Abrams, Aaron; Hower, Valerie 2010-01-01 428 VARIATIONAL ESTIMATES FOR DISCRETE SCHR Mathematics Websites...
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Geometric Approach to ML Estimation With Incomplete Data: Application to Semi Reilly, James P. 94 Energy Levels of "Hydrogen Atom" in Discrete Time Dynamics Quantum Physics...
A quantitative description of mesh dependence for the discretization ...
that coming from a ferromagnetic spin energy. The critical case can be regarded as an interpolation between the two. Key words. spatial discretization, singularly
Efficient energy stable schemes with spectral discretization in space ...
We construct energy stable schemes for the time discretization of the highly nonlinear ... shape) in order to achieve a well-defined energy for the system.
Discretization schemes for diffusion operators on general meshes
Herbin, Rapha�le
: Navier Stokes equations Flow in porous media, Darcy equation. discretization of -div( u)) A can Supplementary constraint from the oil reservoir simulation community: cell centred schemes transport equations
Lowest-rank Solutions of Continuous and Discrete Lyapunov ...
Ziyan Luo
Oct 9, 2012 ... Abstract: The low-rank solutions of continuous and discrete Lyapunov equations are of great importance but generally difficult to achieve in�...
The robust stabilization problem for discrete-time descriptor systems
Claudiu Dinicu
Sep 23, 2014 ... Abstract: We investigate the robust stabilization problem for the descriptor discrete-time systems and build an optimal solution in the case when�...
Sandia National Laboratories: atmospheric chemistry
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and atmospheric chemistry that is expected to benefit auto and engine manufacturers, oil and gas utilities, and other industries that employ combustion models. A paper...
ELSEVIER AtmosphericResearch 38 (1995) 207-235 ATMOSPHERIC
Moelders, Nicole
ELSEVIER AtmosphericResearch 38 (1995) 207-235 ATMOSPHERIC RESEARCH On the parameterization of ice and water substance mixing ratio fields were only strongly altered by turning off the ice phase of these schemes includes ice processes. But in mid- latitudes and also in tropics the ice phase is an important
ATMOSPHERIC ELSEVIER AtmosphericResearch 44 (1997) 231-241
Reading, University of
ATMOSPHERIC RESEARCH ELSEVIER AtmosphericResearch 44 (1997) 231-241 Error analysis of backscatter;accepted 14 February 1997 Abstract Ice sphere backscatter has been calculated using both Mie theory as a reasonable approximation for rv 1997 Elsevier Science B.V. 1. Introduction Cirrus clouds play
Information storage capacity of discrete spin systems
Beni Yoshida
Understanding the limits imposed on information storage capacity of physical systems is a problem of fundamental and practical importance which bridges physics and information science. There is a well-known upper bound on the amount of information that can be stored reliably in a given volume of discrete spin systems which are supported by gapped local Hamiltonians. However, all the previously known systems were far below this theoretical bound, and it remained open whether there exists a gapped spin system that saturates this bound. Here, we present a construction of spin systems which saturate this theoretical limit asymptotically by borrowing an idea from fractal properties arising in the Sierpinski triangle. Our construction provides not only the best classical error-correcting code which is physically realizable as the energy ground space of gapped frustration-free Hamiltonians, but also a new research avenue for correlated spin phases with fractal spin configurations.
Discrete solitons and vortices on anisotropic lattices
Kevrekidis, P.G. [Department of Mathematics and Statistics, University of Massachusetts, Amherst, Massachusetts 01003-4515 (United States); Frantzeskakis, D.J. [Department of Physics, University of Athens, Panepistimiopolis, Zografos, Athens 15784 (Greece); Carretero-Gonzalez, R. [Nonlinear Dynamical Systems Group, Department of Mathematics and Statistics, and Computational Science Research Center, San Diego State University, San Diego, California 92182-7720 (United States); Malomed, B.A. [Department of Interdisciplinary Studies, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel); Bishop, A.R. [Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
We consider the effects of anisotropy on solitons of various types in two-dimensional nonlinear lattices, using the discrete nonlinear Schroedinger equation as a paradigm model. For fundamental solitons, we develop a variational approximation that predicts that broad quasicontinuum solitons are unstable, while their strongly anisotropic counterparts are stable. By means of numerical methods, it is found that, in the general case, the fundamental solitons and simplest on-site-centered vortex solitons ('vortex crosses') feature enhanced or reduced stability areas, depending on the strength of the anisotropy. More surprising is the effect of anisotropy on the so-called 'super-symmetric' intersite-centered vortices ('vortex squares'), with the topological charge S equal to the square's size M: we predict in an analytical form by means of the Lyapunov-Schmidt theory, and confirm by numerical results, that arbitrarily weak anisotropy results in dramatic changes in the stability and dynamics in comparison with the degenerate, in this case, isotropic, limit.
A Vertical Grid Module for Baroclinic Models of the Atmosphere
Drake, John B [ORNL
The vertical grid of an atmospheric model assigns dynamic and thermo- dynamic variables to grid locations. The vertical coordinate is typically not height but one of a class of meteorological variables that vary with atmo- spheric conditions. The grid system is chosen to further numerical approx- imations of the boundary conditions so that the system is terrain following at the surface. Lagrangian vertical coordinates are useful in reducing the numerical errors from advection processes. That the choices will effect the numercial properties and accuracy is explored in this report. A MATLAB class for Lorentz vertical grids is described and applied to the vertical struc- ture equation and baroclinic atmospheric circulation. A generalized meteo- rolgoical coordinate system is developed which can support ?, isentropic ? vertical coordinate, or Lagrangian vertical coordinates. The vertical atmo- spheric column is a MATLAB class that includes the kinematic and ther- modynamic variables along with methods for computing geopoentials and terms relevant to a 3D baroclinc atmospheric model.
From Discrete Specifications to Hybrid Control1 Paulo Tabuada
Pappas, George J.
@seas.upenn.edu Abstract A great challenge for modern systems theory is the de- sign of controllers for continuous systems inside physical devices has resulted in great challenges for modern and future systems and control theory given a discrete- time controllable linear system and a discrete specifica- tion (in the form
Model Transformation with Hierarchical Discrete-Event Control
Model Transformation with Hierarchical Discrete- Event Control Thomas Huining Feng Electrical permission. #12;Model Transformation with Hierarchical Discrete-Event Control by Huining Feng B.S. (Nanjing Date Date University of California, Berkeley Spring 2009 #12;Model Transformation with Hierarchical
Directed Control of Discrete Event Systems: Optimization Based Approach
Kumar, Ratnesh
Directed Control of Discrete Event Systems: Optimization Based Approach J. Huang and R. Kumar an optimal director. Keywords: Discrete event systems, optimal control, supervisory control, directed control sense for plants that are executor of controllable events. In this paper we develop an optimization
Faugeras, Blaise
EQUILIBRIUM RECONSTRUCTION FROM DISCRETE MAGNETIC MEASUREMENTS IN A TOKAMAK Blaise Faugeras (joint of the equilibrium in a Tokamak from discrete magnetic mea- surements. In order to solve this inverse problem we of a plasma in a Tokamak [1]. The state variable of interest in the modelization of such an equilibrium under
Discrete Wavelet Diffusion for Image Denoising Kashif Rajpoot1
Rajpoot, Nasir
Discrete Wavelet Diffusion for Image Denoising Kashif Rajpoot1 , Nasir Rajpoot2 , J. Alison Noble1 to iterative wavelet shrinkage, but only for (1) MallatZhong dyadic wavelet transform and (2) Haar wavelet shrinkage in the standard discrete wavelet transform (DWT) domain. Two of the major advantages
A DISCRETE WAVELET ANALYSIS OF FREAK WAVES IN THE OCEAN EN-BING LIN AND PAUL C. LIU Received 25 wavelet analysis on a freak wave. We demonstrate several applications of wavelets and discrete and continuous wavelet transforms on the study of a freak wave. A modeling setting for freak waves will also
A Discrete-Event Systems Approach to Modeling Dextrous Manipulation
Graham, Nick
A Discrete-Event Systems Approach to Modeling Dextrous Manipulation S. L. Ricker? N. Sarkar?y K-event systems. The applicability of discrete-event systems to the modeling of dextrous manipulation tasks of the manipulation task, resulting in control discontinuities. The need for tech- niques to facilitate a smooth
University of Michigan and NBER "Identification of Discrete Choice
Presenter: Jeremy Fox University of Michigan and NBER "Identification of Discrete Choice Models;Identification of Discrete Choice Models for Bundles and Binary Games Jeremy T. Fox University of Michigan and NBER Natalia Lazzati University of Michigan March 2014 Abstract We study nonparametric identification
Hefei Institute of Intelligent Machines
importantly, the recognition based on shape feature is also a central problem in those fields such as patternSHAPE MATCHING USING FUZZY DISCRETE PARTICLE SWARM OPTIMIZATION* Ji-Xiang Du1, 2 De-Shuang Huang1 based on fuzzy discrete particle swarm optimization (FDPSO) is proposed. Based on fuzzy theory and PSO
Institute of Operations Research Discrete Optimization and Logistics
Al Hanbali, Ahmad
Institute of Operations Research Discrete Optimization and Logistics 1 Prof. Dr. Stefan Nickel � Health Care Logistics: Overview Health Care Logistics 11/28/2013 #12;Institute of Operations Research Discrete Optimization and Logistics 2 Prof. Dr. Stefan Nickel � Health Care Logistics: Overview Health Care
Cryptanalysing the Critical Group: Efficiently Solving Biggs's Discrete Logarithm Problem
Cryptanalysing the Critical Group: Efficiently Solving Biggs's Discrete Logarithm Problem Simon R Kingdom firstname.lastname@example.com November 7, 2008 Abstract Biggs has recently proposed the critical group that the discrete log problem can be efficiently solved in Biggs's groups. Thus this class of groups is not suitable
Video Denoising and Simplification Via Discrete Regularization on Graphs
Paris-Sud XI, Universit� de
Video Denoising and Simplification Via Discrete Regularization on Graphs Mahmoud Ghoniem, Youssef algorithms for video de- noising and simplification based on discrete regularization on graphs. The main difference between video and image denoising is the temporal redundancy in video sequences. Recent works
ISS-Lyapunov Functions for Discontinuous Discrete-Time Systems
Paris-Sud XI, Universit� de
1 ISS-Lyapunov Functions for Discontinuous Discrete-Time Systems Lars Gr�une and Christopher M. Kellett Abstract Input-to-State Stability (ISS) and the ISS-Lyapunov function have proved to be useful- ous discrete-time dynamics, we investigate ISS-Lyapunov functions for such systems. ISS-Lyapunov
Space Science : Atmosphere Greenhouse Effect
Johnson, Robert E.
Space Science : Atmosphere Greenhouse Effect Part-5a Solar + Earth Spectrum IR Absorbers Grey Atmosphere Greenhouse Effect #12;Radiation: Solar and Earth Surface B"(T) Planck Ideal Emission Integrate at the carbon cycle #12;However, #12;Greenhouse Effect is Complex #12;PLANETARY ENERGY BALANCE G+W fig 3-5
Constant pressure and temperature discrete-time Langevin molecular dynamics
Niels Gr�nbech-Jensen; Oded Farago
We present a new and improved method for simultaneous control of temperature and pressure in molecular dynamics simulations with periodic boundary conditions. The thermostat-barostat equations are build on our previously developed stochastic thermostat, which has been shown to provide correct statistical configurational sampling for any time step that yields stable trajectories. Here, we extend the method and develop a set of discrete-time equations of motion for both particle dynamics and system volume in order to seek pressure control that is insensitive to the choice of the numerical time step. The resulting method is simple, practical, and efficient. The method is demonstrated through direct numerical simulations of two characteristic model systems - a one dimensional particle chain for which exact statistical results can be obtained and used as benchmarks, and a three dimensional system of Lennard-Jones interacting particles simulated in both solid and liquid phases. The results, which are compared against the method of Kolb & Dunweg, show that the new method behaves according to the objective, namely that acquired statistical averages and fluctuations of configurational measures are accurate and robust against the chosen time step applied to the simulation.
Ch4. Atmosphere and Surface Energy Balances
Pan, Feifei
;Energy Pathways #12;Solar radiation transfer in the atmosphere Solar radiation Reflection Atmosphere or performing any work. #12;Solar radiation transfer in the atmosphere Solar radiation Reflection Transmission or water. #12;Solar radiation transfer in the atmosphere Solar radiation Reflection Transmission Atmosphere
Overturning and wind driven circulation in a low-order ocean-atmosphere model
van Veen, Lennaert
july 2002 Abstract A low-order ocean-atmosphere model is presented which combines coupling through heat exchange at the interface and wind stress forcing. The coupling terms are derived from the boundary conditions and the forcing terms of the constituents. Both the ocean and the atmosphere model are based
Modeling Atmospheric Aerosols V. Rao Kotamarthi
Modeling Atmospheric Aerosols V. Rao Kotamarthi and Yan Feng Climate Research Section Environmental Science Division Argonne National Laboratory #12;Outline Atmospheric Aerosols and gas phase heterogeneous reactions Regional Scales and Atmospheric Aerosols Regional Scale Aerosols: Ganges Valley Aerosol
An efficient permeability scaling-up technique applied to the discretized flow equations
Urgelli, D.; Ding, Yu [Institut Francais du Petrole, Rueil Malmaison (France)
Grid-block permeability scaling-up for numerical reservoir simulations has been discussed for a long time in the literature. It is now recognized that a full permeability tensor is needed to get an accurate reservoir description at large scale. However, two major difficulties are encountered: (1) grid-block permeability cannot be properly defined because it depends on boundary conditions; (2) discretization of flow equations with a full permeability tensor is not straightforward and little work has been done on this subject. In this paper, we propose a new method, which allows us to get around both difficulties. As the two major problems are closely related, a global approach will preserve the accuracy. So, in the proposed method, the permeability up-scaling technique is integrated in the discretized numerical scheme for flow simulation. The permeability is scaled-up via the transmissibility term, in accordance with the fluid flow calculation in the numerical scheme. A finite-volume scheme is particularly studied, and the transmissibility scaling-up technique for this scheme is presented. Some numerical examples are tested for flow simulation. This new method is compared with some published numerical schemes for full permeability tensor discretization where the full permeability tensor is scaled-up through various techniques. Comparing the results with fine grid simulations shows that the new method is more accurate and more efficient.
atmospheric aerosol source-receptor: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
coefficient is 0.5 and then 1.0 2. For the same conditions calculate the H Weber, Rodney 6 Secondary organic aerosol 1. Atmospheric chemical mechanism for production...
An Excursion-Theoretic Approach to Stability of Discrete-Time Stochastic Hybrid Systems
Chatterjee, Debasish, E-mail: firstname.lastname@example.com [ETH Zuerich, ETL I19 (Switzerland); Pal, Soumik, E-mail: email@example.com [University of Washington, Department of Mathematics (United States)
We address stability of a class of Markovian discrete-time stochastic hybrid systems. This class of systems is characterized by the state-space of the system being partitioned into a safe or target set and its exterior, and the dynamics of the system being different in each domain. We give conditions for L{sub 1}-boundedness of Lyapunov functions based on certain negative drift conditions outside the target set, together with some more minor assumptions. We then apply our results to a wide class of randomly switched systems (or iterated function systems), for which we give conditions for global asymptotic stability almost surely and in L{sub 1}. The systems need not be time-homogeneous, and our results apply to certain systems for which functional-analytic or martingale-based estimates are difficult or impossible to get.
Fragmentation Energetics of Clusters Relevant to Atmospheric...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
of Clusters Relevant to Atmospheric New Particle Formation. Fragmentation Energetics of Clusters Relevant to Atmospheric New Particle Formation. Abstract: The exact mechanisms by...
Large-scale optimal power flow: Effects of initialization, decoupling and discretization
Papalexopoulos, A.D.; Imparato, C.F.; Wu, F.F.
The optimal power flow has entered a new era since the introduction of second-order methods. These methods have renewed hopes for its on-line application in Energy Management Systems. This paper reports on some of the results of tests of a second-order OPF method. The testing was conducted using a 1500 bus network, under a variety of loading conditions. Three issues were studied: Sensitivity of OPF solutions with respect to the starting points used in the solution; Accuracy of the active/reactive decoupled approach to OPF solution; Effects of discretization of transformer taps on the OPF solutions.
Determining the significance of associations between two series of discrete events : bootstrap methods /
Niehof, Jonathan T.; Morley, Steven K.
We review and develop techniques to determine associations between series of discrete events. The bootstrap, a nonparametric statistical method, allows the determination of the significance of associations with minimal assumptions about the underlying processes. We find the key requirement for this method: one of the series must be widely spaced in time to guarantee the theoretical applicability of the bootstrap. If this condition is met, the calculated significance passes a reasonableness test. We conclude with some potential future extensions and caveats on the applicability of these methods. The techniques presented have been implemented in a Python-based software toolkit.
Generalized discrete orbit function transforms of affine Weyl groups
Tomasz Czy?ycki; Ji?� Hrivn�k
The affine Weyl groups with their corresponding four types of orbit functions are considered. Two independent admissible shifts, which preserve the symmetries of the weight and the dual weight lattices, are classified. Finite subsets of the shifted weight and the shifted dual weight lattices, which serve as a sampling grid and a set of labels of the orbit functions, respectively, are introduced. The complete sets of discretely orthogonal orbit functions over the sampling grids are found and the corresponding discrete Fourier transforms are formulated. The eight standard one-dimensional discrete cosine and sine transforms form special cases of the presented transforms.
Multidimensional electron-photon transport with standard discrete ordinates codes
Drumm, C.R.
A method is described for generating electron cross sections that are compatible with standard discrete ordinates codes without modification. There are many advantages of using an established discrete ordinates solver, e.g. immediately available adjoint capability. Coupled electron-photon transport capability is needed for many applications, including the modeling of the response of electronics components to space and man-made radiation environments. The cross sections have been successfully used in the DORT, TWODANT and TORT discrete ordinates codes. The cross sections are shown to provide accurate and efficient solutions to certain multidimensional electronphoton transport problems.
Information storage capacity of discrete spin systems
Yoshida, Beni, E-mail: firstname.lastname@example.com
Understanding the limits imposed on information storage capacity of physical systems is a problem of fundamental and practical importance which bridges physics and information science. There is a well-known upper bound on the amount of information that can be stored reliably in a given volume of discrete spin systems which are supported by gapped local Hamiltonians. However, all the previously known systems were far below this theoretical bound, and it remained open whether there exists a gapped spin system that saturates this bound. Here, we present a construction of spin systems which saturate this theoretical limit asymptotically by borrowing an idea from fractal properties arising in the Sierpinski triangle. Our construction provides not only the best classical error-correcting code which is physically realizable as the energy ground space of gapped frustration-free Hamiltonians, but also a new research avenue for correlated spin phases with fractal spin configurations. -- Highlights: �We propose a spin model with fractal ground states and study its coding properties. �We show that the model asymptotically saturates a theoretical limit on information storage capacity. �We discuss its relations to various theoretical physics problems.
Environmental Chemistry II (Atmospheric Chemistry)
Dibble, Theodore
SYLLABUS FOR Environmental Chemistry II (Atmospheric Chemistry) FCH 511 Fall 2013 Theodore S/explaining the trends in J as a function of altitude and solar zenith angle. The second involves analyzing real
Spiga, Aymeric
THE MARTIAN ATMOSPHERIC BOUNDARY LAYER A. Petrosyan,1 B. Galperin,2 S. E. Larsen,3 S. R. Lewis,4 A [Haberle et al., 1993a; Larsen et al., 2002; Hinson et al., 2008]. At night, convection is inhibited
Atmospheric science and power production
Randerson, D. (ed.)
This is the third in a series of scientific publications sponsored by the US Atomic Energy Commission and the two later organizations, the US Energy Research and Development Adminstration, and the US Department of Energy. The first book, Meteorology and Atomic Energy, was published in 1955; the second, in 1968. The present volume is designed to update and to expand upon many of the important concepts presented previously. However, the present edition draws heavily on recent contributions made by atmospheric science to the analysis of air quality and on results originating from research conducted and completed in the 1970s. Special emphasis is placed on how atmospheric science can contribute to solving problems relating to the fate of combustion products released into the atmosphere. The framework of this book is built around the concept of air-quality modeling. Fundamentals are addressed first to equip the reader with basic background information and to focus on available meteorological instrumentation and to emphasize the importance of data management procedures. Atmospheric physics and field experiments are described in detail to provide an overview of atmospheric boundary layer processes, of how air flows around obstacles, and of the mechanism of plume rise. Atmospheric chemistry and removal processes are also detailed to provide fundamental knowledge on how gases and particulate matter can be transformed while in the atmosphere and how they can be removed from the atmosphere. The book closes with a review of how air-quality models are being applied to solve a wide variety of problems. Separate analytics have been prepared for each chapter.
Laser Atmospheric Studies with VERITAS
C. M. Hui; for the VERITAS collaboration
As a calibrated laser pulse propagates through the atmosphere, the amount of Rayleigh-scattered light arriving at the VERITAS telescopes can be calculated precisely. This technique was originally developed for the absolute calibration of ultra-high-energy cosmic-ray fluorescence telescopes but is also applicable to imaging atmospheric Cherenkov telescopes (IACTs). In this paper, we present two nights of laser data taken with the laser at various distances away from the VERITAS telescopes and compare it to Rayleigh scattering simulations.
Atmospheric Radiation Measurement Program Science Plan
Ackerman, T
The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: Maintain the data record at the fixed ARM sites for at least the next five years. Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. Implement and evaluate an operational methodology to calculate broad-band heating rates in the atmospheric columns at the ARM sites. Develop and implement methodologies to use ARM data more effectively to test atmospheric models, both at the cloud-resolving model scale and the GCM scale. Use these methodologies to diagnose cloud parameterization performance and then refine these parameterizations to improve the accuracy of climate model simulations. In addition, the ARM Program is actively developing a new ARM Mobile Facility (AMF) that will be available for short deployments (several months to a year or more) in climatically important regions. The AMF will have much of the same instrumentation as the remote facilities at ARM's Tropical Western Pacific and the North Slope of Alaska sites. Over time, this new facility will extend ARM science to a much broader range of conditions for model testing.
Representative Atmospheric Plume Development for Elevated Releases
Eslinger, Paul W.; Lowrey, Justin D.; McIntyre, Justin I.; Miley, Harry S.; Prichard, Andrew W.
An atmospheric explosion of a low-yield nuclear device will produce a large number of radioactive isotopes, some of which can be measured with airborne detection systems. However, properly equipped aircraft may not arrive in the region where an explosion occurred for a number of hours after the event. Atmospheric conditions will have caused the radioactive plume to move and diffuse before the aircraft arrives. The science behind predicting atmospheric plume movement has advanced enough that the location of the maximum concentrations in the plume can be determined reasonably accurately in real time, or near real time. Given the assumption that an aircraft can follow a plume, this study addresses the amount of atmospheric dilution expected to occur in a representative plume as a function of time past the release event. The approach models atmospheric transport of hypothetical releases from a single location for every day in a year using the publically available HYSPLIT code. The effective dilution factors for the point of maximum concentration in an elevated plume based on a release of a non-decaying, non-depositing tracer can vary by orders of magnitude depending on the day of the release, even for the same number of hours after the release event. However, the median of the dilution factors based on releases for 365 consecutive days at one site follows a power law relationship in time, as shown in Figure S-1. The relationship is good enough to provide a general rule of thumb for estimating typical future dilution factors in a plume starting at the same point. However, the coefficients of the power law function may vary for different release point locations. Radioactive decay causes the effective dilution factors to decrease more quickly with the time past the release event than the dilution factors based on a non-decaying tracer. An analytical expression for the dilution factors of isotopes with different half-lives can be developed given the power law expression for the non-decaying tracer. If the power-law equation for the median dilution factor, Df, based on a non-decaying tracer has the general form Df=a?�t?^(-b) for time t after the release event, then the equation has the form Df=e^(-?t)�a�t^(-b) for a radioactive isotope, where ? is the decay constant for the isotope.
A Wavelet-Based Methodology for Grinding Wheel Condition Monitoring
Liao, T. W. [Louisiana State University; Ting, C.F. [Louisiana State University; Qu, Jun [ORNL; Blau, Peter Julian [ORNL
Grinding wheel surface condition changes as more material is removed. This paper presents a wavelet-based methodology for grinding wheel condition monitoring based on acoustic emission (AE) signals. Grinding experiments in creep feed mode were conducted to grind alumina specimens with a resinoid-bonded diamond wheel using two different conditions. During the experiments, AE signals were collected when the wheel was 'sharp' and when the wheel was 'dull'. Discriminant features were then extracted from each raw AE signal segment using the discrete wavelet decomposition procedure. An adaptive genetic clustering algorithm was finally applied to the extracted features in order to distinguish different states of grinding wheel condition. The test results indicate that the proposed methodology can achieve 97% clustering accuracy for the high material removal rate condition, 86.7% for the low material removal rate condition, and 76.7% for the combined grinding conditions if the base wavelet, the decomposition level, and the GA parameters are properly selected.
Design of discrete-time filters for efficient implementation
Wei, Dennis
The cost of implementation of discrete-time filters is often strongly dependent on the number of non-zero filter coefficients or the precision with which the coefficients are represented. This thesis addresses the design ...
Resolution of grain scale interactions using the Discrete Element Method
Johnson, Scott M. (Scott Matthew), 1978-
Granular materials are an integral part of many engineering systems. Currently, a popular tool for numerically investigating granular systems is the Discrete Element Method (DEM). Nearly all implementations of the DEM, ...
Discrete Feature Approach for Heterogeneous Reservoir Production Enhancement
Dershowitz, William S.; Curran, Brendan; Einstein, Herbert; LaPointe, Paul; Shuttle, Dawn; Klise, Kate
The report presents summaries of technology development for discrete feature modeling in support of the improved oil recovery (IOR) for heterogeneous reservoirs. In addition, the report describes the demonstration of these technologies at project study sites.
Optimization With Parity Constraints: From Binary Codes to Discrete Integration
Bejerano, Gill
Optimization With Parity Constraints: From Binary Codes to Discrete Integration Stefano Ermon guarantees on the quality of the solution found. Markov Chain Monte Carlo [17, 21, 32] and Importance
Embed and Project: Discrete Sampling with Universal Hashing
Bejerano, Gill
Embed and Project: Discrete Sampling with Universal Hashing Stefano Ermon, Carla P. Gomes Dept Markov Chain Monte Carlo (MCMC) methods. MCMC techniques are a specialized form of local search that only
Analysis of steel silo structures on discrete supports�
Li, Hongyu
The objective of this thesis is to broaden current knowledge of the strength and buckling/collapse of shells, with special reference to steel silo structures on discrete supports, and thus to provide design guidance of ...
Direct measurement of yield stress of discrete materials
S. H. Ebrahimnazhad Rahbari; J. Vollmer; S. Herminghaus; M. Brinkmann
We present a novel computational method for direct measurement of yield stress of discrete materials. The method is well-suited for the measurement of jamming phase diagram of a wide range of discrete particle systems such as granular materials, foams, and colloids. We further successfully apply the method to evaluate the jamming phase diagram of wet granular material in order to demonstrates the applicability of the model.
Isolation of Discrete Nanoparticle-DNA Conjugates for Plasmonic Applications
Alivisatos, Paul; Claridge, Shelley A.; Liang, Huiyang W.; Basu, Sourav Roger; Frechet, Jean M.J.; Alivisatos, A. Paul
Discrete DNA-gold nanoparticle conjugates with DNA lengths as short as 15 bases for both 5 nm and 20 nm gold particles have been purified by anion-exchange HPLC. Conjugates comprising short DNA (<40 bases) and large gold particles (>_ 20 nm) are difficult to purify by other means, and are potential substrates for plasmon coupling experiments. Conjugate purity is demonstrated by hybridizing complementary conjugates to form discrete structures, which are visualized by TEM.
Infrared Spectroscopy of Discrete Uranyl Anion Complexes
Gary S. Groenewold; Anita K. Gianotto; Michael E. McIlwain; Michael J. Van Stipdonk; Michael Kullman; Travis J. Cooper; David T. Moore; Nick Polfer; Jos Oomens; Ivan Infante; Lucas Visscher; Bertrand Siboulet; Wibe A. de Jong
The Free-Electron Laser for Infrared Experiments, FELIX, was used to study the wavelength-resolved multiphoton dissociation of discrete, gas phase uranyl (UO22+) complexes containing a single anionic ligand (A), with or without ligated solvent molecules (S). The apparent uranyl antisymmetric and symmetric stretching frequencies were measured for complexes with general formula [UO2A(S)n]+, where A was either hydroxide, methoxide or acetate, S was water, ammonia, acetone or acetonitrile, and n = 0-2. The values for the antisymmetric stretching frequency for uranyl ligated with only an anion ([UO2A]+) were as low or lower than measurements for [UO2]2+ ligated with as many as five strong neutral donor ligands, and are comparable to solution phase values. This result was surprising because initial DFT calculations using B3LYP predicted values that were 30 � 40 cm-1 higher, consistent with intuition but not with the data. Modification of the basis set and use of alternative functionals improved computational accuracy for the methoxide and acetate complexes, but calculated values for the hydroxide were greater than the measurement regardless of the computational method used. Attachment of a neutral donor ligand S to [UO2A]+ produced [UO2AS]+, which resulted only very modest changes to the uranyl frequency, and did not universally shift values lower. DFT calculations for [UO2AS]+ were in accord with trends in the data, and showed that attachment of the solvent was accommodated by weakening of the U-anion bond as well as the uranyl. When uranyl frequencies were compared for [UO2AS]+ species having different solvent neutrals, values decreased with increasing neutral nucleophilicity.
Infared Spectroscopy of Discrete Uranyl Anion Complexes
Groenewold, G. S.; Gianotto, Anita K.; McIIwain, Michael E.; Van Stipdonk, Michael J.; Kullman, Michael; Moore, David T.; Polfer, Nick; Oomens, Jos; Infante, Ivan A.; Visscher, Lucas; Siboulet, Bertrand; De Jong, Wibe A.
The Free-Electron Laser for Infrared Experiments (FELIX) w 1 as used to study the wavelength-resolved multiple photon photodissociation of discrete, gas phase uranyl (UO2 2 2+) complexes containing a single anionic ligand (A), with or without ligated solvent molecules (S). The uranyl antisymmetric and symmetric stretching frequencies were measured for complexes with general formula [UO2A(S)n]+, where A was either hydroxide, methoxide, or acetate; S was water, ammonia, acetone, or acetonitrile; and n = 0-3. The values for the antisymmetric stretching frequency for uranyl ligated with only an anion ([UO2A]+) were as low or lower than measurements for [UO2]2+ ligated with as many as five strong neutral donor ligands, and are comparable to solution phase values. This result was surprising because initial DFT calculations predicted values that were 30�40 cm-1 higher, consistent with intuition but not with the data. Modification of the basis sets and use of alternative functionals improved computational accuracy for the methoxide and acetate complexes, but calculated values for the hydroxide were greater than the measurement regardless of the computational method used. Attachment of a neutral donor ligand S to [UO2A]+ produced [UO2AS]+, which produced only very modest changes to the uranyl antisymmetric stretch frequency, and did not universally shift the frequency to lower values. DFT calculations for [UO2AS]+ were in accord with trends in the data, and showed that attachment of the solvent was accommodated by weakening of the U-anion bond as well as the uranyl. When uranyl frequencies were compared for [UO2AS]+ species having different solvent neutrals, values decreased with increasing neutral nucleophilicity.
On Discrete Symmetries and Torsion Homology in F-Theory
Christoph Mayrhofer; Eran Palti; Oskar Till; Timo Weigand
We study the relation between discrete gauge symmetries in F-theory compactifications and torsion homology on the associated Calabi-Yau manifold. Focusing on the simplest example of a $\\mathbb Z_2$ symmetry, we show that there are two physically distinct ways that such a discrete gauge symmetry can arise. First, compactifications of M-Theory on Calabi-Yau threefolds which support a genus-one fibration with a bi-section are known to be dual to six-dimensional F-theory vacua with a $\\mathbb Z_2$ gauge symmetry. We show that the resulting five-dimensional theories do not have a $\\mathbb Z_2$ symmetry but that the latter emerges only in the F-theory decompactification limit. Accordingly the genus-one fibred Calabi-Yau manifolds do not exhibit discrete torsion. Associated to the bi-section fibration is a Jacobian fibration which does support a section. Compactifying on these related but distinct varieties does lead to a $\\mathbb Z_2$ symmetry in five dimensions and, accordingly, we find explicitly an associated discrete torsion. We identify the expected particle and membrane system of the discrete symmetry in terms of wrapped M2 and M5 branes and present a field-theory description of the physics for both cases in terms of circle reductions of six-dimensional theories. Our results and methods generalise straightforwardly to larger discrete symmetries and to four-dimensional compactifications.
An implicit finite element method for discrete dynamic fracture
Jobie M. Gerken
A method for modeling the discrete fracture of two-dimensional linear elastic structures with a distribution of small cracks subject to dynamic conditions has been developed. The foundation for this numerical model is a plane element formulated from the Hu-Washizu energy principle. The distribution of small cracks is incorporated into the numerical model by including a small crack at each element interface. The additional strain field in an element adjacent to this crack is treated as an externally applied strain field in the Hu-Washizu energy principle. The resulting stiffness matrix is that of a standard plane element. The resulting load vector is that of a standard plane element with an additional term that includes the externally applied strain field. Except for the crack strain field equations, all terms of the stiffness matrix and load vector are integrated symbolically in Maple V so that fully integrated plane stress and plane strain elements are constructed. The crack strain field equations are integrated numerically. The modeling of dynamic behavior of simple structures was demonstrated within acceptable engineering accuracy. In the model of axial and transverse vibration of a beam and the breathing mode of vibration of a thin ring, the dynamic characteristics were shown to be within expected limits. The models dominated by tensile forces (the axially loaded beam and the pressurized ring) were within 0.5% of the theoretical values while the shear dominated model (the transversely loaded beam) is within 5% of the calculated theoretical value. The constant strain field of the tensile problems can be modeled exactly by the numerical model. The numerical results should therefore, be exact. The discrepancies can be accounted for by errors in the calculation of frequency from the numerical results. The linear strain field of the transverse model must be modeled by a series of constant strain elements. This is an approximation to the true strain field, so some error is expected.
Oscillations of solar atmosphere neutrinos
G. L. Fogli; E. Lisi; A. Mirizzi; D. Montanino; P. D. Serpico
The Sun is a source of high energy neutrinos (E > 10 GeV) produced by cosmic ray interactions in the solar atmosphere. We study the impact of three-flavor oscillations (in vacuum and in matter) on solar atmosphere neutrinos, and calculate their observable fluxes at Earth, as well as their event rates in a kilometer-scale detector in water or ice. We find that peculiar three-flavor oscillation effects in matter, which can occur in the energy range probed by solar atmosphere neutrinos, are significantly suppressed by averaging over the production region and over the neutrino and antineutrino components. In particular, we find that the relation between the neutrino fluxes at the Sun and at the Earth can be approximately expressed in terms of phase-averaged ``vacuum'' oscillations, dominated by a single mixing parameter (the angle theta_23).
Cumulant expansions for atmospheric flows
Ait-Chaalal, Farid; Meyer, Bettina; Marston, J B
The equations governing atmospheric flows are nonlinear, and consequently the hierarchy of cumulant equations is not closed. But because atmospheric flows are inhomogeneous and anisotropic, the nonlinearity may manifests itself only weakly through interactions of mean fields with disturbances such as thermals or eddies. In such situations, truncations of the hierarchy of cumulant equations hold promise as a closure strategy. We review how truncations at second order can be used to model and elucidate the dynamics of turbulent atmospheric flows. Two examples are considered. First, we study the growth of a dry convective boundary layer, which is heated from below, leading to turbulent upward energy transport and growth of the boundary layer. We demonstrate that a quasilinear truncation of the equations of motion, in which interactions of disturbances among each other are neglected but interactions with mean fields are taken into account, can successfully capture the growth of the convective boundary layer. Seco...
Ionisation in atmospheres of brown dwarfs and extrasolar planets VI: Properties of large-scale discharge events
Bailey, R L; Hodos, G; Bilger, C; Stark, C R
Mineral clouds in substellar atmospheres play a special role as a catalyst for a variety of charge processes. If clouds are charged, the surrounding environment becomes electrically activated, and ensembles of charged grains are electrically discharging (e.g. by lightning), which significantly infuences the local chemistry creating conditions similar to those thought responsible for life in early planetary atmospheres. We note that such lightning discharges contribute also to the ionisation state of the atmosphere. We apply scaling laws for electrical discharge processes from laboratory measurements and numerical experiments to Drift-Phoenix model atmosphere results to model the discharge's propagation downwards (as lightning) and upwards (as sprites) through the atmospheric clouds. We evaluate the spatial extent and energetics of lightning discharges. The atmospheric volume affected (e.g. by increase of temperature or electron number) is larger in a brown dwarf atmosphere ($10^8 -~10^{10}$m$^3$) than in a gi...
Rucklidge, Alastair
become fragmented and twisted, and where they generate the necessary energy to heat the solar coronaHEATING THE ATMOSPHERE ABOVE SUNSPOTS David Alexander and Neal E. Hurlburt Lockheed Martin Solar, University of Cambridge, Cambridge, CB3 9EW, UK Abstract We present our results of a hybrid model of sunspots
Space Science: Atmosphere Thermal Structure
Johnson, Robert E.
Space Science: Atmosphere Part -2 Thermal Structure Review tropospheres Absorption of Radiation Adiabatic Lapse Rate ~ 9 K/km Slightly smaller than our estimate Pressure ~3000ft under ocean surface thickness (positive up) is the solar zenith angle Fs is the solar energy flux at frequency (when
Discrete KP equation with self-consistent sources
Adam Doliwa; Runliang Lin
We show that the discrete Kadomtsev-Petviashvili (KP) equation with sources obtained recently by the "source generalization" method can be incorporated into the squared eigenfunction symmetry extension procedure. Moreover, using the known correspondence between Darboux-type transformations and additional independent variables, we demonstrate that the equation with sources can be derived from Hirota's discrete KP equations but in a space of higher dimension. In this way we uncover the origin of the source terms as coming from multidimensional consistency of the Hirota system itself.
Methodology for characterizing modeling and discretization uncertainties in computational simulation
This research effort focuses on methodology for quantifying the effects of model uncertainty and discretization error on computational modeling and simulation. The work is directed towards developing methodologies which treat model form assumptions within an overall framework for uncertainty quantification, for the purpose of developing estimates of total prediction uncertainty. The present effort consists of work in three areas: framework development for sources of uncertainty and error in the modeling and simulation process which impact model structure; model uncertainty assessment and propagation through Bayesian inference methods; and discretization error estimation within the context of non-deterministic analysis.
Discrete Intrinsic Redshifts from Quasars to Normal Galaxies
M. B. Bell
It is pointed out that the discrete velocities found by Tifft in galaxies are harmonically related to the discrete intrinsic redshifts found in quasars. All are harmonically related to the constant 0.062 +/- 0.001, and this is the fourth independent analysis in which the redshift increment 0.062 has been shown to be significant. It is concluded that there is a quantized component in the redshift of both quasars and galaxies that has a common origin and is unlikely to be Doppler-related.
Discrete canonical analysis of three dimensional gravity with cosmological constant
J. Berra-Montiel; J. E. Rosales-Quintero
We discuss the interplay between standard canonical analysis and canonical discretization in three-dimensional gravity with cosmological constant. By using the Hamiltonian analysis, we find that the continuum local symmetries of the theory are given by the on-shell space-time diffeomorphisms, which at the action level, corresponds to the Kalb-Ramond transformations. At the time of discretization, although this symmetry is explicitly broken, we prove that the theory still preserves certain gauge freedom generated by a constant curvature relation in terms of holonomies and the Gauss's law in the lattice approach.
Sulfuryl fluoride in the global atmosphere
Muhle, J.
The first calibrated high-frequency, high-precision, in situ atmospheric and archived air measurements of the fumigant sulfuryl fluoride (SO[subscript 2]F[subscript 2]) have been made as part of the Advanced Global Atmospheric ...
ATMOSPHERIC SCIENCE LETTERS Atmos. Sci. Let. (2012)
Gerber, Edwin
ATMOSPHERIC SCIENCE LETTERS Atmos. Sci. Let. (2012) Published online in Wiley Online Library using National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP) concentrations and sea- surface temperatures (SSTs). These integrations enable the relative role of ozone
1997 Atmospheric Chemistry Colloquium for Emerging Senior Scientists
Paul H. Wine
DOE's Atmospheric Chemistry Program is providing partial funding for the Atmospheric Chemistry Colloquium for Emerging Senior Scientists (ACCESS) and FY 1997 Gordon Research Conference in Atmospheric Chemistry
atmospheric nitrogen fluorescence: Topics by E-print Network
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Websites Summary: Greenhouse Effect and Atmospheric Warming Atmosphere absorbs heat energy A real greenhouse traps heatCh4. Atmosphere and Surface Energy Balances...
atmospheric energy redistribution: Topics by E-print Network
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16 Ch4. Atmosphere and Surface Energy Balances Geosciences Websites Summary: Greenhouse Effect and Atmospheric Warming Atmosphere absorbs heat energy A real greenhouse traps...
atmospheric pressure surface: Topics by E-print Network
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K. 27 Ch4. Atmosphere and Surface Energy Balances Geosciences Websites Summary: Greenhouse Effect and Atmospheric Warming Atmosphere absorbs heat energy A real greenhouse traps...
Radar range measurements in the atmosphere.
Doerry, Armin Walter
The earth's atmosphere affects the velocity of propagation of microwave signals. This imparts a range error to radar range measurements that assume the typical simplistic model for propagation velocity. This range error is a function of atmospheric constituents, such as water vapor, as well as the geometry of the radar data collection, notably altitude and range. Models are presented for calculating atmospheric effects on radar range measurements, and compared against more elaborate atmospheric models.
Atmos. Chem. Phys., 3, 469474, 2003 www.atmos-chem-phys.org/acp/3/469/ Atmospheric
Paris-Sud XI, Universit� de
with -pinene, limonene or catechol and OH radicals with toluene or limonene, respec- tively. The aerosols were sampled on filters and exposed to humidified NO2 mixtures under atmospheric conditions. The estimated
Proof of the Atmospheric Greenhouse Effect
Smith, Arthur P
A recently advanced argument against the atmospheric greenhouse effect is refuted. A planet without an infrared absorbing atmosphere is mathematically constrained to have an average temperature less than or equal to the effective radiating temperature. Observed parameters for Earth prove that without infrared absorption by the atmosphere, the average temperature of Earth's surface would be at least 33 K lower than what is observed.
Atmospheric Lifetime of Fossil Fuel Carbon Dioxide
Scherer, Norbert F.
Atmospheric Lifetime of Fossil Fuel Carbon Dioxide David Archer,1 Michael Eby,2 Victor Brovkin,3 released from combustion of fossil fuels equilibrates among the various carbon reservoirs of the atmosphere literature on the atmospheric lifetime of fossil fuel CO2 and its impact on climate, and we present initial
GPU accelerated simulations of 3D deterministic particle transport using discrete ordinates method
Gong Chunye, E-mail: email@example.com [School of Computer Science, National University of Defense Technology, Changsha 410073 (China); Liu Jie, E-mail: firstname.lastname@example.com [School of Computer Science, National University of Defense Technology, Changsha 410073 (China); Chi Lihua [School of Computer Science, National University of Defense Technology, Changsha 410073 (China); Huang Haowei [Institut fuer Informatik, Technische Universitaet Muenchen, D-85748 Garching, Munich (Germany); Fang Jingyue [School of Physics and Mathematics, National University of Defense Technology, Changsha 410073 (China); Gong Zhenghu [School of Computer Science, National University of Defense Technology, Changsha 410073 (China)
Graphics Processing Unit (GPU), originally developed for real-time, high-definition 3D graphics in computer games, now provides great faculty in solving scientific applications. The basis of particle transport simulation is the time-dependent, multi-group, inhomogeneous Boltzmann transport equation. The numerical solution to the Boltzmann equation involves the discrete ordinates (S{sub n}) method and the procedure of source iteration. In this paper, we present a GPU accelerated simulation of one energy group time-independent deterministic discrete ordinates particle transport in 3D Cartesian geometry (Sweep3D). The performance of the GPU simulations are reported with the simulations of vacuum boundary condition. The discussion of the relative advantages and disadvantages of the GPU implementation, the simulation on multi GPUs, the programming effort and code portability are also reported. The results show that the overall performance speedup of one NVIDIA Tesla M2050 GPU ranges from 2.56 compared with one Intel Xeon X5670 chip to 8.14 compared with one Intel Core Q6600 chip for no flux fixup. The simulation with flux fixup on one M2050 is 1.23 times faster than on one X5670.
Atmospheric-pressure plasma jet
Selwyn, Gary S. (Los Alamos, NM)
Atmospheric-pressure plasma jet. A .gamma.-mode, resonant-cavity plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250.degree. C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two concentric cylindrical electrodes are employed to generate a plasma in the annular region therebetween. A "jet" of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly shaping the rf-powered electrode. Because of the atmospheric pressure operation, no ions survive for a sufficiently long distance beyond the active plasma discharge to bombard a workpiece, unlike low-pressure plasma sources and conventional plasma processing methods.
Continuum Representation for Simulating Discrete Events of Battery Operation
Panchagnula, Mahesh
the discrete events in the cycling studies of lithium-ion batteries as a continuum event has been proposed-order pseudo-two-dimensional lithium-ion battery model that has several coupled and nonlinear partial that are currently fol- lowed for the modeling of charge/discharge cycles of lithium-ion batteries involve different
Fractal algebras of discretization sequences Steffen Roch (TU Darmstadt)
Potts, Daniel
Abstract Fractal algebras of discretization sequences Steffen Roch (TU Darmstadt) First a warning: Fractality, in the sense of these lectures, has nothing to do with fractal geometries or broken dimensions or other involved things. Rather, the notion fractal algebra had been chosen in order to emphasize
Power Control for Discrete-Input Block-Fading Channels
Guillén i Fàbregas, Albert
. K. Rasmussen CUED / F-INFENG / TR 582 August 2007 #12;#12;1 Power Control for Discrete-Input Block-Fading Channels Khoa D. Nguyen, Albert Guill´en i F`abregas and Lars K. Rasmussen Abstract We consider power systems employing orthogonal frequency division multiplexing. K. D. Nguyen and L. K. Rasmussen
DISCRETE AND CONTINUOUS Website: http://AIMsciences.org DYNAMICAL SYSTEMS
Shiau, LieJune
well known fact: When there is dry friction, the force necessary to put the system into motion. 806815 OPERATOR SPLITTING METHOD FOR FRICTION CONSTRAINED DYNAMICAL SYSTEMS LieJune Shiau Department-discretization of those relations mod- eling a class of dynamical systems with friction was discussed. The main goal
Two samples test for discrete power-law distributions
Bessi, Alessandro
Power-law distributions occur in wide variety of physical, biological, and social phenomena. In this paper, we propose a statistical hypothesis test based on the log-likelihood ratio to assess whether two samples of discrete data are drawn from the same power-law distribution.
Energy-Efficient Discrete Cosine Transform on Ronald Scrofano
Jang, Ju-Wook
Energy-Efficient Discrete Cosine Transform on FPGAs Ronald Scrofano Department of Computer Science is brought to mobile devices, it becomes important that it is possible to calculate the DCT in an energy-efficient the DCT with a linear array of PEs. This design is optimized for energy efficiency. We analyze the energy
Multivariable Discrete Time Repetitive Control System Hammoud Saari1
Boyer, Edmond
Multivariable Discrete Time Repetitive Control System Hammoud Saari1 and Bernard Caron2 1 SETRAM, France firstname.lastname@example.com, firstname.lastname@example.com Keywords: Repetitive Control, Multivariable), Ahn et al. (2007) and Saari et al. (2010)). Most of their works were focused on the problem
Time-Variant Channel Equalization via Discrete Prolate Spheroidal Sequences
Zemen, Thomas
are processed by an inverse discrete Fourier transform (DFT) to obtain an orthogonal frequency division Devices department (RCD), part of the Siemens AG Austria, Program and System Engineering (PSE) and the Telecommunications Research Center Vienna (ftw.) in the I0 project. Thomas Zemen was with Siemens AG Austria when he
The Discrete Wavelet Transform and Wavelet Synopses Minos Garofalakis
Garofalakis, Minos
The Discrete Wavelet Transform and Wavelet Synopses Minos Garofalakis Technical University of Crete firstname.lastname@example.com SYNONYMS None. DEFINITION Wavelets are a useful mathematical tool for hierarchically decomposing functions in ways that are both efficient and theoretically sound. Broadly speaking, the wavelet
Generic Average Modeling and Simulation of Discrete Controllers
modeling of discrete controllers for PWM power conversion systems. The method applies a section be advantageous to have the capability of running AC analysis of digitally controlled power systems on a general the simulation of digitally controlled power conversion systems on general-purpose circuit simulators
Discrete fracture modeling for fractured reservoirs using Voronoi grid blocks
Gross, Matthew Edward
or pseudofracture groups modeled in their own grid blocks. Discrete Fracture Modeling (DFN) is still a relatively new field, and most research on it up to this point has been done with Delaunay tessellations. This research investigates an alternative approach using...
Wave-packet continuum discretization for quantum scattering
O. A. Rubtsova; V. I. Kukulin; V. N. Pomerantsev
A general approach to a solution of few- and many-body scattering problems based on a continuum-discretization procedure is described in detail. The complete discretization of continuous spectrum is realized using stationary wave packets which are the normalized states constructed from exact non-normalized continuum states. Projecting the wave functions and all scattering operators like $t$-matrix, resolvent, etc. on such a wave-packet basis results in a formulation of quantum scattering problem entirely in terms of discrete elements and linear equations with regular matrices. It is demonstrated that there is a close relation between the above stationary wave packets and pseudostates which are employed often to approximate the scattering states with a finite $L_2$ basis. Such a fully discrete treatment of complicated few- and many-body scattering problems leads to significant simplification of their practical solution. Also we get finite-dimensional approximations for complicated operators like effective interactions between composite particles constructed via the Feshbach-type projection formalism. As illustrations to this general approach we consider several important particular problems including multichannel scattering and scattering in the three-nucleon system within the Faddeev framework.
Spectral discretization of Darcy's equations with pressure dependent porosity
Paris-Sud XI, Universit� de
Spectral discretization of Darcy's equations with pressure dependent porosity by Mejdi Aza�iez1 and the pressure p of the fluid. This system is an extension of Darcy's equations, which model the flow of the resulting system of equations which takes into account the axisymmetry of the domain and of the flow. We
Mortar spectral element discretization of Darcy's equations in nonhomogeneous medium
Paris-Sud XI, Universit� de
Mortar spectral element discretization of Darcy's equations in nonhomogeneous medium Mouna Daadaa Cedex 05 France. email@example.com 4 mai 2010 Abstract : We consider Darcy's equations. They turn out to be in good coherency with the theoretical results. R�esum�e : Les �equations de Darcy mod
Error Exponent for Discrete Memoryless Multiple-Access Channels
Anastasopoulos, Achilleas
Error Exponent for Discrete Memoryless Multiple-Access Channels by Ali Nazari A dissertation Bayraktar Associate Professor Jussi Keppo #12;c Ali Nazari 2011 All Rights Reserved #12;To my parents. ii Becky Turanski, Nancy Goings, Michele Feldkamp, Ann Pace, Karen Liska and Beth Lawson for efficiently
Coded Adaptive Linear Precoded Discrete Multitone Over PLC Channel
Boyer, Edmond
Coded Adaptive Linear Precoded Discrete Multitone Over PLC Channel Fahad Syed Muhammmad, Jean- DMT system is presented in the power line communication (PLC) context with a loading algorithm which spectral density constraint. Using a multipath model of PLC channel, it is shown that the proposed coded
Controlling Wild Mobile Robots Using Virtual Gates and Discrete Transitions
LaValle, Steven M.
Controlling Wild Mobile Robots Using Virtual Gates and Discrete Transitions Leonardo Bobadilla purposely design them to execute wild motions, which means each will strike every open set infinitely often, "wildly behaving" robots that move more-or-less straight until a wall is contacted. They then pick
Discrete Mathematics: Methods and Challenges Combinatorics is a fundamental mathematical discipline as well as an essential component of
Shamir, Ron
Discrete Mathematics: Methods and Challenges Noga Alon Abstract Combinatorics is a fundamental connection between Discrete Mathematics and Theoretical Computer Science, and the rapid development two centuries. The tight connection between Discrete Mathematics and Theoretical Computer Science
Linearisation of the (M,K)-reduced non-autonomous discrete periodic KP equation
Shinsuke Iwao
The (M,K)-reduced non-autonomous discrete KP equation is linearised on the Picard group of an algebraic curve. As an application, we construct theta function solutions to the initial value problem of some special discrete KP equation.
Limited Model Information Control Design for Linear Discrete-Time Systems with Stochastic Parameters
Johansson, Karl Henrik
Limited Model Information Control Design for Linear Discrete-Time Systems with Stochastic systems with stochastically varying parameters. Recently, there have been studies in optimal control subsystems' parameters. There have been many studies in optimal control design for linear discrete
Multiphase autoresonant excitations in discrete nonlinear Schrdinger systems Y. Gopher and L. Friedland
Friedland, Lazar
Multiphase autoresonant excitations in discrete nonlinear Schr�dinger systems Y. Gopher and L September 2005 Large amplitude, multiphase solutions of periodic discrete nonlinear Schr�dinger NLS systems of an external parameter driving frequency . Numerical examples of excitation of multiphase waves and periodic
Analysis of Dual Consistency for Discontinuous Galerkin Discretizations of Source Terms
Darmofal, David L.
The effects of dual consistency on discontinuous Galerkin discretizations of solution and solution gradient dependent source terms are examined. Two common discretizations are analyzed: the standard weighting technique for ...
Fault tolerant control allocation in systems with fixed magnitude discrete controls�
Marwaha, Monika
as discrete controls. However, discrete controls constitute a different class of problems than proportional controls as they can take only binary values, unlike proportional controls which can take many values. Two nonlinear control laws based on Structured...
Sebastian Schunert; Yousry Y. Azmy; Damien Fournier
We present a comprehensive error estimation of four spatial discretization schemes of the two-dimensional Discrete Ordinates (SN) equations on Cartesian grids utilizing a Method of Manufactured Solution (MMS) benchmark suite based on variants of Larsen�s benchmark featuring different orders of smoothness of the underlying exact solution. The considered spatial discretization schemes include the arbitrarily high order transport methods of the nodal (AHOTN) and characteristic (AHOTC) types, the discontinuous Galerkin Finite Element method (DGFEM) and the recently proposed higher order diamond difference method (HODD) of spatial expansion orders 0 through 3. While AHOTN and AHOTC rely on approximate analytical solutions of the transport equation within a mesh cell, DGFEM and HODD utilize a polynomial expansion to mimick the angular flux profile across each mesh cell. Intuitively, due to the higher degree of analyticity, we expect AHOTN and AHOTC to feature superior accuracy compared with DGFEM and HODD, but at the price of potentially longer grind times and numerical instabilities. The latter disadvantages can result from the presence of exponential terms evaluated at the cell optical thickness that arise from the semianalytical solution process. This work quantifies the order of accuracy and the magnitude of the error of all four discretization methods for different optical thicknesses, scattering ratios and degrees of smoothness of the underlying exact solutions in order to verify or contradict the aforementioned intuitive expectation.
Accounting for StreamAquifer Interactions in the State-Space Discretization of the
Szilagyi, Jozsef
MilyukovNash Cascade for Streamflow Forecasting Jozsef Szilagyi1 Abstract: A sample-data system discretization
A coarse entropy-rigidity theorem and discrete length-volume inequalities
Kinneberg, Kyle Edward
A discrete length-volume inequality . . . . . . . .v 3 Length-volume inequalities revisitedlength-volume inequality for cubes . . . . . . . . . . . .
An Isometric Dynamics for a Causal Set Approach to Discrete Quantum Gravity
Stan Gudder
We consider a covariant causal set approach to discrete quantum gravity. We first review the microscopic picture of this approach. In this picture a universe grows one element at a time and its geometry is determined by a sequence of integers called the shell sequence. We next present the macroscopic picture which is described by a sequential growth process. We introduce a model in which the dynamics is governed by a quantum transition amplitude. The amplitude satisfies a stochastic and unitary condition and the resulting dynamics becomes isometric. We show that the dynamics preserves stochastic states. By "doubling down" on the dynamics we obtain a unitary group representation and a natural energy operator. These unitary operators are employed to define canonical position and momentum operators.
An Infrared Spectral Library for Atmospheric Environmental Monitoring...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
An Infrared Spectral Library for Atmospheric Environmental Monitoring. An Infrared Spectral Library for Atmospheric Environmental Monitoring. Abstract: Infrared (IR) spectroscopy...
atmospheric research community: Topics by E-print Network
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University Corporation for Atmospheric Research Geosciences Websites Summary: University Corporation for Atmospheric Research CIGNA DENTAL PREFERRED PROVIDER INSURANCE EFFECTIVE...
DISCRETE EXTENDED KALMAN FILTER ON LIE GROUPS Guillaume Bourmaud, Rmi Mgret, Audrey Giremus and Yannick Berthoumieu
Paris-Sud XI, Universit� de
DISCRETE EXTENDED KALMAN FILTER ON LIE GROUPS Guillaume Bourmaud, R�mi M�gret, Audrey Giremus, 33405 Talence cedex, France ABSTRACT In this paper, we generalize the Discrete Extended Kalman Filter (D called Discrete Extended Kalman Filter on Lie Groups (D- LG-EKF). It assumes that the posterior
Numerical study of natural convection in a vertical porous annulus with discrete heating
Lopez, John M.
Numerical study of natural convection in a vertical porous annulus with discrete heating M. Sankar online 20 December 2010 Keywords: Natural convection Annulus Discrete heating Porous medium Radii ratio to discrete heating. The outer wall is maintained iso- thermally at a lower temperature, while the top
CERNA WORKING PAPER SERIES Patent quality and value in discrete and cumulative innovation
Paris-Sud XI, Universit� de
1 CERNA WORKING PAPER SERIES Patent quality and value in discrete and cumulative innovation Justus,version2-16Nov2010 #12;2 Patent Quality and Value in Discrete and Cumulative Innovation Cerna Working the relationship between patent quality and patent value in discrete and cumulative innovation. Using factor
Smith, Alice E.
is not known. Instead, we consider the more realistic assumption of discrete cost-reliability data sets expressions for cost-reliability curves, we consider discrete cost-reliability data sets for each componentOPTIMAL RELIABILITY ALLOCATION IN SERIES-PARALLEL SYSTEMS FROM COMPONENTS' DISCRETE COST
Discrete-Time Pricing and Optimal Exercise of American Perpetual Warrants in the Geometric Random Walk Model
Vanderbei, Robert J., E-mail: firstname.lastname@example.com [Princeton University, Department of Operations Research and Financial Engineering (United States); P Latin-Small-Letter-Dotless-I nar, Mustafa C., E-mail: firstname.lastname@example.com [Bilkent University, Department of Industrial Engineering (Turkey); Bozkaya, Efe B. [Sabanc Latin-Small-Letter-Dotless-I University, Faculty of Administrative Sciences (Turkey)] [Sabanc Latin-Small-Letter-Dotless-I University, Faculty of Administrative Sciences (Turkey)
An American option (or, warrant) is the right, but not the obligation, to purchase or sell an underlying equity at any time up to a predetermined expiration date for a predetermined amount. A perpetual American option differs from a plain American option in that it does not expire. In this study, we solve the optimal stopping problem of a perpetual American option (both call and put) in discrete time using linear programming duality. Under the assumption that the underlying stock price follows a discrete time and discrete state Markov process, namely a geometric random walk, we formulate the pricing problem as an infinite dimensional linear programming (LP) problem using the excessive-majorant property of the value function. This formulation allows us to solve complementary slackness conditions in closed-form, revealing an optimal stopping strategy which highlights the set of stock-prices where the option should be exercised. The analysis for the call option reveals that such a critical value exists only in some cases, depending on a combination of state-transition probabilities and the economic discount factor (i.e., the prevailing interest rate) whereas it ceases to be an issue for the put.
Lowenstein, Andrew; Miller, Jeffrey; Gruendeman, Peter; DaSilva, Michael
An air conditioner comprises a plurality of plates arranged in a successively stacked configuration with portions thereof having a spaced apart arrangement, and defining between successive adjacent pairs of plates at the spaced apart portions a first and second series of discrete alternating passages wherein a first air stream is passed through the first series of passages and a second air stream is passed through the second series of passages; and said stacked configuration of plates forming integrally therewith a liquid delivery means for delivering from a source a sufficient quantity of a liquid to the inside surfaces of the first series of fluid passages in a manner which provides a continuous flow of the liquid from a first end to a second end of the plurality of plates while in contact with the first air stream.
Pulse atmospheric fluidized bed combustion
Not Available
The overall objective of the program is the development of a pulsed atmospheric fluidized-bed combustion (PAFBC) technology to burn coal and to provide heat and steam to commercial, institutional, and small industrial applications at a reasonable price in an environmentally acceptable manner. During this reporting period, a total of eight shakedown and debugging coal combustion tests were performed in the AFBC. A start-up procedure was established, system improvements implemented, and preliminary material and heat balances made based on these tests. The pulse combustor for the AFBC system was fabricated and installed and a series of tests was conducted on the system. 17 figs., 5 tabs.
NETL SOFC: Atmospheric Pressure Systems
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AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Saleshttp://www.fnal.gov/directorate/nalcal/nalcal02_07_05_files/nalcal.gif Directorate -AdvancedMIRTBD525AdaptingWaterTerryAtmospheric
Simulation and Comparison of Particle Injection in an Indoor Environment Using the Species Transport and Discrete Phase Models
Zheng, Zhongquan C.; Wei, Zhenglun A.; Bennett, James S.; Yang, Xiaofan
In simulating fluid/solid-particle multiphase -flows, various methods are available. One approach is the combined Euler-Lagrange method, which simulates the fluid phase flow in the Eulerian framework and the discrete phase (particle) motion in the Lagrangian framework simultaneously. The Lagrangian approach, where particle motion is determined by the current state of the fluid phase flow, is also called the discrete phase model (DPM), in the context of numerical flow simulation. In this method, the influence of the particle motions on the fluid flow can be included (two-way interactions) but are more commonly excluded (one-way interactions, when the discrete phase concentration is dilute. The other approach is to treat the particle number concentration as a continuous species, a necessarily passive quantity determined by the fluid flow, with no influences from the particles on the fluid flow (one-way interactions only), except to the extent the discrete phase �continuum� alters the overall fluid properties, such as density. In this paper, we compare these two methods with experimental data for an indoor environmental chamber. The effects of injection particle numbers and the related boundary conditions are investigated. In the Euler-Lagrange interaction or DPM model for incompressible flow, the Eulerian continuous phase is governed by the Reynolds-averaged N-S (RANS) equations. The motions of particles are governed by Newton�s second law. The effects of particle motions are communicated to the continuous phase through a force term in the RANS equations. The second formulation is a pure Eulerian type, where only the particle-number concentration is addressed, rather than the motion of each individual particle. The fluid flow is governed by the same RANS equations without the particle force term. The particle-number concentration is simulated by a species transport equation. Comparisons among the models and with experimental and literature data are presented. Particularly, results with different numbers of released particles in the DPM will be investigated.
A Thermal Discrete Element Analysis of EU Solid Breeder Blanket subjected to Neutron Irradiation
Yixiang Gan; Francisco Hernandez; Dorian Hanaor; Ratna Annabattula; Marc Kamlah; Pavel Pereslavtsev
Due to neutron irradiation, solid breeder blankets are subjected to complex thermo-mechanical conditions. Within one breeder unit, the ceramic breeder bed is composed of spherical-shaped lithium orthosilicate pebbles, and as a type of granular material, it exhibits strong coupling between temperature and stress fields. In this paper, we study these thermo-mechanical problems by developing a thermal discrete element method (Thermal-DEM). This proposed simulation tool models each individual ceramic pebble as one element and considers grain-scale thermo-mechanical interactions between elements. A small section of solid breeder pebble bed in HCPB is modelled using thousands of individual pebbles and subjected to volumetric heating profiles calculated from neutronics under ITER-relevant conditions. We consider heat transfer at the grain-scale between pebbles through both solid-to-solid contacts and the interstitial gas phase, and we calculate stresses arising from thermal expansion of pebbles. The overall effective conductivity of the bed depends on the resulting compressive stress state during the neutronic heating. The thermal-DEM method proposed in this study provides the access to the grain-scale information, which is beneficial for HCPB design and breeder material optimization, and a better understanding of overall thermo-mechanical responses of the breeder units under fusion-relevant conditions.
Satoshi Ohya; Makoto Sakamoto; Motoi Tachibana
In this paper we argue that boundary condition may run with energy scale. As an illustrative example, we consider one-dimensional quantum mechanics for a spinless particle that freely propagates in the bulk yet interacts only at the origin. In this setting we find the renormalization group flow of U(2) family of boundary conditions exactly. We show that the well-known scale-independent subfamily of boundary conditions are realized as fixed points. We also discuss the duality between two distinct boundary conditions from the renormalization group point of view. Generalizations to conformal mechanics and quantum graph are also discussed.
On Estimating Conditional Conservatism
Ball, Ray
The concept of conditional conservatism (asymmetric earnings timeliness) has provided new insight into financial reporting and stimulated considerable research since Basu (1997). Patatoukas and Thomas (2011) report bias ...
Global discretization of continuous attributes as preprocessing for machine learning
Chmielewski, M. R.; Grzymala-Busse, Jerzy W.
continuous attribute is partitioning its domain into equal width intervals is called Equal Interval Width Method. A method of attribute discretization through adaptive discretization was proposed in [3]. The domain of an attribute is first partitioned... Interval Frequency Class Analysis Width per Interval Entropy Method GM 68.0 59.0 73.0 69.0 rocks 57.5 54.2 55.6 53.0 iris 91.5 86.7 82.0 95.3 bank 77.3 95.5 84.9 97.0 hsv-r 42.5 35.8 46.7 48.3 bupa 41.9 39.7 41.3 42.5 glass 54.7 49.5 56.1 60.3 wave 99.4 99...
A study of discrete and continuum joint modeling techniques
Jung, J.; Brown, S.R.
This paper presents the results of a numerical and experimental study in which finite element and discrete element techniques were used to analyze a layered polycarbonate plate model subjected to uniaxial compression. Also, the two analysis techniques were used to compute the response of an eight meter diameter drift in jointed-rock. The drift was subjected to in-situ and far-field induced thermal stresses. The finite element analyses used a continuum rock model to represent the jointed-rock. A comparison of the analyses showed that the finite element continuum joint model consistently predicted less joint slippage than did the discrete element analyses, although far-field displacements compared well.
The discrete Kalman filtering approach for seismic signals deconvolution
Kurniadi, Rizal; Nurhandoko, Bagus Endar B. [Departement of Physics Intitut Teknologi Bandung, Jl. Ganesha 10 Bandung (Indonesia)
Seismic signals are a convolution of reflectivity and seismic wavelet. One of the most important stages in seismic data processing is deconvolution process; the process of deconvolution is inverse filters based on Wiener filter theory. This theory is limited by certain modelling assumptions, which may not always valid. The discrete form of the Kalman filter is then used to generate an estimate of the reflectivity function. The main advantage of Kalman filtering is capability of technique to handling continually time varying models and has high resolution capabilities. In this work, we use discrete Kalman filter that it was combined with primitive deconvolution. Filtering process works on reflectivity function, hence the work flow of filtering is started with primitive deconvolution using inverse of wavelet. The seismic signals then are obtained by convoluting of filtered reflectivity function with energy waveform which is referred to as the seismic wavelet. The higher frequency of wavelet gives smaller wave length, the graphs of these results are presented.
Quantum Mechanics and Discrete Time from "Timeless" Classical Dynamics
H. -T. Elze
We study classical Hamiltonian systems in which the intrinsic proper time evolution parameter is related through a probability distribution to the physical time, which is assumed to be discrete. - This is motivated by the ``timeless'' reparametrization invariant model of a relativistic particle with two compactified extradimensions. In this example, discrete physical time is constructed based on quasi-local observables. - Generally, employing the path-integral formulation of classical mechanics developed by Gozzi et al., we show that these deterministic classical systems can be naturally described as unitary quantum mechanical models. The emergent quantum Hamiltonian is derived from the underlying classical one. It is closely related to the Liouville operator. We demonstrate in several examples the necessity of regularization, in order to arrive at quantum models with bounded spectrum and stable groundstate.
A discrete model for compressible flows in heterogeneous media
Le Metayer, O., E-mail: firstname.lastname@example.com [IUSTI, UMR CNRS 6595, Universite Aix-Marseille I, Technopole de Chateau Gombert, 5 Rue E. Fermi, 13453 Marseille Cedex 13 (France); SMASH project, INRIA, 2004 route des Lucioles, 06902 Sophia Antipolis (France); Massol, A., E-mail: email@example.com [AIRBUS Operations SAS, Coc Powerplant, EDET30, M0112/5, 316 Route de Bayonne, 31060 Toulouse Cedex 09 (France); Favrie, N., E-mail: firstname.lastname@example.com [IUSTI, UMR CNRS 6595, Universite Aix-Marseille I, Technopole de Chateau Gombert, 5 Rue E. Fermi, 13453 Marseille Cedex 13 (France); SMASH project, INRIA, 2004 route des Lucioles, 06902 Sophia Antipolis (France); Hank, S., E-mail: email@example.com [IUSTI, UMR CNRS 6595, Universite Aix-Marseille I, Technopole de Chateau Gombert, 5 Rue E. Fermi, 13453 Marseille Cedex 13 (France); SMASH project, INRIA, 2004 route des Lucioles, 06902 Sophia Antipolis (France)
This work deals with the building of a discrete model able to describe and to predict the evolution of complex gas flows in heterogeneous media. In many physical applications, large scales numerical simulation is no longer possible because of a lack of computing resources. Indeed the medium topology may be complex due to the presence of many obstacles (walls, pipes, equipments, geometric singularities etc.). Aircraft powerplant compartments are examples where topology is complex due to the presence of pipes, ducts, coolers and other equipment. Other important examples are gas explosions and large scale dispersion of hazardous materials in urban places, cities or underground involving obstacles such as buildings and various infrastructures. In all cases efficient safety responses are required. Then a new discrete model is built and solved in reasonable execution times for large cells volumes including such obstacles. Quantitative comparisons between experimental and numerical results are shown for different significant test cases, showing excellent agreement.
Weakly bound molecules trapped with discrete scaling symmetries
Yusuke Nishida; Dean Lee
When the scattering length is proportional to the distance from the center of the system, two particles are shown to be trapped about the center. Furthermore, their spectrum exhibits discrete scale invariance, whose scale factor is controlled by the slope of the scattering length. While this resembles the Efimov effect, our system has a number of advantages when realized with ultracold atoms. We also elucidate how the emergent discrete scaling symmetry is violated for more than two bosons, which may shed new light on Efimov physics. Our system thus serves as a tunable model system to investigate universal physics involving scale invariance, quantum anomaly, and renormalization group limit cycle, which are important in a broad range of quantum physics.
Monte Carlo solution of a semi-discrete transport equation
Urbatsch, T.J.; Morel, J.E.; Gulick, J.C.
The authors present the S{sub {infinity}} method, a hybrid neutron transport method in which Monte Carlo particles traverse discrete space. The goal of any deterministic/stochastic hybrid method is to couple selected characters from each of the methods in hopes of producing a better method. The S{sub {infinity}} method has the features of the lumped, linear-discontinuous (LLD) spatial discretization, yet it has no ray-effects because of the continuous angular variable. They derive the S{sub {infinity}} method for the solid-state, mono-energetic transport equation in one-dimensional slab geometry with isotropic scattering and an isotropic internal source. They demonstrate the viability of the S{sub {infinity}} method by comparing their results favorably to analytic and deterministic results.
The Discrete Geometry of a Small Causal Diamond
Mriganko Roy; Debdeep Sinha; Sumati Surya
We study the discrete causal set geometry of a small causal diamond in a curved spacetime using the average abundance of k-element chains or total orders in the underlying causal set C. We begin by obtaining the first order curvature corrections to the flat spacetime expression for the abundance using Riemann normal coordinates. For fixed spacetime dimension this allows us to find a new expression for the discrete scalar curvature of C as well as the time-time component of its Ricci tensor in terms of the abundances of k-chains. We also find a new dimension estimator for C which replaces the flat spacetime Myrheim-Meyer estimator in generic curved spacetimes.
Directed assembly of discrete gold nanoparticle groupings usingbranched DNA scaffolds
Claridge, Shelley A.; Goh, Sarah L.; Frechet, Jean M.J.; Williams, Shara C.; Micheel, Christine M.; Alivisatos, A. Paul
The concept of self-assembled dendrimers is explored for the creation of discrete nanoparticle assemblies. Hybridization of branched DNA trimers and nanoparticle-DNA conjugates results in the synthesis of nanoparticle trimer and tetramer complexes. Multiple tetramer architectures are investigated, utilizing Au-DNA conjugates with varying secondary structural motifs. Hybridization products are analyzed by gel electrophoresis, and discrete bands are observed corresponding to structures with increasing numbers of hybridization events. Samples extracted from each band are analyzed by transmission electron microscopy, and statistics compiled from micrographs are used to compare assembly characteristics for each architecture. Asymmetric structures are also produced in which both 5 and 10 nm Au particles are assembled on branched scaffolds.
Stability measurements of PPL atmospheric pressure arc
Roquemore, L.; Zweben, S.J. [Princeton Plasma Physics Lab., NJ (United States); Wurden, G.A. [Los Alamos National Lab., NM (United States)
Experiments on the stability of atmospheric pressure arcs have been started at PPL to understand and improve the performance of arc furnaces used for processing applications in metallurgy and hazardous waste treatment. Previous studies have suggested that the violent instabilities in such arcs may be due to kink modes. A 30 kW, 500 Amp CW DC experimental arc furnace was constructed with a graphite cathode and a molten steel anode. The arc plasma is diagnosed with 4000 frames/sec digital camera, Hall probes, and voltage and current monitors. Under certain conditions, the arc exhibits an intermittent helical instability, with the helix rotating at {approx}600 Hz. The nature of the instability is investigated. A possible instability mechanism is the self-magnetic field of the arc, with saturation occurring due to inhomogeneous heating in a helical arc. The effect of external DC and AC magnetic fields on the instability is investigated. Additionally, arc deflection due to external transverse magnetic field is investigated. The deflection angle is found to be proportional to the applied field, and is in good agreement with a simple model of the {rvec J} x {rvec b} force on the arc jet.
Scaling behavior of discretization errors in renormalization and improvement constants
Bhattacharya, T; Lee, W; Sharpe, S R; Bhattacharya, Tanmoy; Gupta, Rajan; Lee, Weonjong; Sharpe, Stephen R.
Non-perturbative results for improvement and renormalization constants needed for on-shell and off-shell O(a) improvement of bilinear operators composed of Wilson fermions are presented. The calculations have been done in the quenched approximation at beta=6.0, 6.2 and 6.4. To quantify residual discretization errors we compare our data with results from other non-perturbative calculations and with one-loop perturbation theory.
Discrete quadratic solitons with competing second-harmonic components
Setzpfandt, Frank; Pertsch, Thomas [Institute of Applied Physics, Abbe Center of Photonics, Friedrich-Schiller-Universitaet Jena, Max-Wien-Platz 1, D-07743 Jena (Germany); Sukhorukov, Andrey A. [Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra, 0200 ACT (Australia)
We describe families of discrete solitons in quadratic waveguide arrays supported by competing cascaded nonlinear interactions between one fundamental and two second-harmonic modes. We characterize the existence, stability, and excitation dynamics of these solitons and show that their features may resemble those of solitons in saturable media. Our results also demonstrate that a power threshold may appear for soliton formation, leading to a suppression of beam self-focusing which explains recent experimental observations.
Evans, Thomas M [ORNL; Joubert, Wayne [ORNL; Hamilton, Steven P [ORNL; Johnson, Seth R [ORNL; Turner, John A [ORNL; Davidson, Gregory G [ORNL; Pandya, Tara M [ORNL
In this paper we describe and demonstrate a discrete ordinates sweep algorithm on GPUs. This sweep algorithm is nested within a multilevel comunication-based decomposition based on energy. We demonstrated the effectiveness of this algorithm on detailed three-dimensional critical experiments and PWR lattice problems. For these problems we show improvement factors of 4 6 over conventional communication-based, CPU-only sweeps. These sweep kernel speedups resulted in a factor of 2 total time-to-solution improvement.
Deriving Spin within a discrete-time theory
Erasmo Recami; Giovanni Salesi
We prove that the classical theory with a discrete time (chronon) is a particular case of a more general theory in which spinning particles are associated with generalized Lagrangians containing time-derivatives of any order (a theory that has been called "Non-Newtonian Mechanics"). As a consequence, we get, for instance, a classical kinematical derivation of Hamiltonian and spin vector for the mentioned chronon theory (e.g., in Caldirola et al.'s formulation).
Entanglement Generation Using Discrete Solitons in Coulomb Crystals
H. Landa; A. Retzker; T. Schaetz; B. Reznik
Laser cooled and trapped ions can crystallize and feature discrete solitons, that are nonlinear, topologically-protected configurations of the Coulomb crystal. Such solitons, as their continuum counterparts, can move within the crystal, while their discreteness leads to the existence of a gap-separated, spatially-localized motional mode of oscillation above the spectrum. Suggesting that these unique properties of discrete solitons can be used for generating entanglement between different sites of the crystal, we study a detailed proposal in the context of state-of-the-art experimental techniques. We analyze the interaction of periodically-driven planar ion crystals with optical forces, revealing the effects of micromotion in radio-frequency traps inherent to such structures, as opposed to linear ion chains. The proposed method requires Doppler cooling of the crystal and sideband cooling of the soliton's localized modes alone. Since the gap separation of the latter is nearly independent of the crystal size, this approach could be particularly useful for producing entanglement and studying system-environment interactions in large, two- and possibly three-dimensional systems.
Heuristic Optimization for the Discrete Virtual Power Plant Dispatch Problem
Petersen, Mette K.; Hansen, Lars H.; Bendtsen, Jan; Edlund, Kristian; Stoustrup, Jakob
We consider a virtual power plant, which is given the task of dispatching a fluctuating power supply to a portfolio of flexible consumers. The flexible consumers are modeled as discrete batch processes, and the associated optimization problem is denoted the discrete virtual power plant dispatch problem (DVPPDP). First, the nondeterministic polynomial time (NP)-completeness of the discrete virtual power plant dispatch problem is proved formally. We then proceed to develop tailored versions of the meta-heuristic algorithms hill climber and greedy randomized adaptive search procedure (GRASP). The algorithms are tuned and tested on portfolios of varying sizes. We find that all the tailored algorithms perform satisfactorily in the sense that they are able to find sub-optimal, but usable, solutions to very large problems (on the order of 105 units) at computation times on the scale of just 10 s, which is far beyond the capabilities of the optimal algorithms we have tested. In particular, GRASP sorted shows with the most promising performance, as it is able to find solutions that are both agile (sorted) and well balanced, and consistently yields the best numerical performance among the developed algorithms.
Atmospheric neutrino flux at INO site
Honda, Morihiro [Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba 277-8582 (Japan)
To illustrate the calculation of the atmospheric neutrino flux, we briefly explain our calculation scheme and important components, such as primary cosmic ray spectra, interaction model, and geomagnetic model. Then, we calculate the atmospheric neutrino flux at INO site in our calculation scheme. We compare the calculated atmospheric neutrino fluxes predicted at INO with those at other major neutrino detector sites, especially that at SK site.
Toxicity of atmospheric aerosols on marine phytoplankton
metals added from these aerosols to the bioassay incubationsreleased to seawater from the aerosol filters after Author4605 CHEMISTRY Atmospheric aerosol deposition CHEMISTRY
Urban Atmospheres captures a unique, synergistic moment
Paulos, Eric
Urban Atmospheres captures a unique, synergistic moment � expanding urban populations, rapid EDITORS Eric Paulos Intel Research firstname.lastname@example.com Tom Jenkins Royal College of Art thomas
Characterizing orbit uncertainty due to atmospheric uncertainty
Wilkins, Matthew Paul
is implemented to model errors in the atmospheric density model. This study shows that the Kalman filter computes a believable and more realistic covariance....
Atmospheric Radiation Measurement Climate Research Facility ...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
improving our understanding of how clouds and atmospheric moisture interact with solar radiation and the effects of these interactions on climate. Photo courtesy Argonne National...
Physics Potential of Future Atmospheric Neutrino Searches
Thomas Schwetz
The potential of future high statistics atmospheric neutrino experiments is considered, having in mind currently discussed huge detectors of various technologies (water Cerekov, magnetized iron, liquid Argon). I focus on the possibility to use atmospheric data to determine the octant of $\\theta_{23}$ and the neutrino mass hierarchy. The sensitivity to the $\\theta_{23}$-octant of atmospheric neutrinos is competitive (or even superior) to long-baseline experiments. I discuss the ideal properties of a fictitious atmospheric neutrino detector to determine the neutrino mass hierarchy.
Super-Kamiokande atmospheric neutrino results
Toshiyuki Toshito; the Super-Kamiokande collaboration
We present atmospheric neutrino results from a 79 kiloton year (1289 days) exposure of the Super-Kamiokande detector. Our data are well explained by $\
atmospheres: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
to optical depth perturbations. In Earth-type atmospheres sustained planetary greenhouse effect with a stable ground surface temperature can only exist at a particular...
atmosphere: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
to optical depth perturbations. In Earth-type atmospheres sustained planetary greenhouse effect with a stable ground surface temperature can only exist at a particular...
atmospherics: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
to optical depth perturbations. In Earth-type atmospheres sustained planetary greenhouse effect with a stable ground surface temperature can only exist at a particular...
Images reveal that atmospheric particles can undergo liquid-liquid phase separations
You, Yuan; Renbaum-Wolff, Lindsay; Carreras-Sospedra, Marc; Hanna, Sarah; Hiranuma, Naruki; Kamal, Saeid; Smith, Mackenzie L.; Zhang, Xiaolu; Weber, Rodney; Shilling, John E.; Dabdub, Donald; Martin, Scot T.; Bertram, Allan K.
A large fraction of submicron atmospheric particles contains both organic material and inorganic salts. As the relative humidity cycles in the atmosphere, these mixed particles can undergo a range of phase transitions, possibly including liquid-liquid phase separation. If liquid-liquid phase separation occurs, the gas-particle partitioning of atmospheric semi-volatile organic compounds, the scattering and absorption of solar radiation, and the uptake of reactive gas species on atmospheric particles will be affected, with important implications for climate predictions. The actual occurrence of these types of phase transitions within individual atmospheric particles has been considered uncertain, in large part because of the absence of observations for real-world samples. Here, using optical and fluorescence microscopy, we observe the coexistence of two non-crystalline phases in particles generated from real-world samples collected on multiple days in Atlanta, Georgia, and in particles generated in the laboratory using atmospheric conditions. These results reveal that atmospheric particles can undergo liquid-liquid phase separations. Using a box model, we show that liquid-liquid phase separation can result in increased concentrations of gas-phase NO3 and N2O5 in the Atlanta region, due to decreased particle uptake of N2O5.
NDE to Manage Atmospheric SCC in Canisters for Dry Storage of Spent Fuel: An Assessment
Meyer, Ryan M.; Pardini, Allan F.; Cuta, Judith M.; Adkins, Harold E.; Casella, Andrew M.; Qiao, Hong (Amy); Larche, Michael R.; Diaz, Aaron A.; Doctor, Steven R.
This report documents efforts to assess representative horizontal (Transuclear NUHOMS�) and vertical (Holtec HI-STORM) storage systems for the implementation of non-destructive examination (NDE) methods or techniques to manage atmospheric stress corrosion cracking (SCC) in canisters for dry storage of used nuclear fuel. The assessment is conducted by assessing accessibility and deployment, environmental compatibility, and applicability of NDE methods. A recommendation of this assessment is to focus on bulk ultrasonic and eddy current techniques for direct canister monitoring of atmospheric SCC. This assessment also highlights canister regions that may be most vulnerable to atmospheric SCC to guide the use of bulk ultrasonic and eddy current examinations. An assessment of accessibility also identifies canister regions that are easiest and more difficult to access through the ventilation paths of the concrete shielding modules. A conceivable sampling strategy for canister inspections is to sample only the easiest to access portions of vulnerable regions. There are aspects to performing an NDE inspection of dry canister storage system (DCSS) canisters for atmospheric SCC that have not been addressed in previous performance studies. These aspects provide the basis for recommendations of future efforts to determine the capability and performance of eddy current and bulk ultrasonic examinations for atmospheric SCC in DCSS canisters. Finally, other important areas of investigation are identified including the development of instrumented surveillance specimens to identify when conditions are conducive for atmospheric SCC, characterization of atmospheric SCC morphology, and an assessment of air flow patterns over canister surfaces and their influence on chloride deposition.
Response of global soil consumption of atmospheric methane to changes in atmospheric climate and nitrogen deposition
Zhuang, Qianlai
Soil consumption of atmospheric methane plays an important secondary role in regulating the atmospheric CH4 budget, next to the dominant loss mechanism involving reaction with the hydroxyl radical (OH). Here we used a ...
Parallization of Stellar Atmosphere Codes
P. Hoeflich
Parallel computing has turned out to be the enabling technology to solve complex physical systems. However, the transition from shared memory, vector computers to massively parallel, distributed memory systems and, recently, to hybrid systems poses new challenges to the scientist. We want to present a cook-book (with a very strong, personal bias) based on our experience with parallization of our existing codes. Some of the general tools and communication libraries are discussed. Our approach includes a mixture of algorithm, domain and physical module based parallization. The advantages, scalability and limitations of each are discussed at some examples. We want show that it becomes easier to write parallel code with increasing complexity of the physical problem making stellar atmosphere codes beyond the classical assumptions very suitable.
Limits to the lunar atmosphere
Morgan, T.H. (National Aeronautics and Space Administration, Washington, D.C. (USA)); Shemansky, D.E. (Univ. of Arizona, Tucson (USA))
The presence of sodium and potassium on the Moon implies that other more abundant species should be present. Volatile molecules like H{sub 2}O are significantly more abundant than sodium in any of the proposed external atmospheric sources. Source mechanisms which derive atoms from the surface should favor abundant elements in the regolith. It is therefore puzzling that the Apollo ultraviolet spectrometer experiment set limits on the density of oxygen of N{sub O} < 5 {times} 10{sup 2} cm{sup {minus}3}, and that the Apollo Lunar Atmospheric Composition Experiment data imply N{sub O} < 50 cm{sup {minus}3} above the subsolar point. These limits are surprisingly small relative to the measured value for sodium. A simple consideration of sources and sinks predicts significantly greater densities of oxygen. It is possible but doubtful that the Apollo measurements occur ed during an epoch in which source rates were small. A preferential loss process for oxygen on the darkside of the Moon is considered in which ionization by electron capture in surface collisions leads to escape through acceleration in the local electric field. Cold trapping in permanently shadowed regions as a net sink is considered and discounted, but the episodic nature of cometary insertion may allow formation of ice layers which act as a stablized source of OH. On the basis of an assumed meteoroid impact source, the authors predict a possible emission brightness of {approximately} 50 R in the OH(A {minus} X)(0,0) band above the lunar bright limb. A very uncertain small comet source of H{sub 2}O could raise this value by more than two orders of magnitude.
"Soft" Continuum Robots: the Interaction of Continuous and Discrete Elements Lara S. Cowan and Ian D. Walker
. Most modern industrial robots are (human) arm-inspired mechanisms with serially arranged discrete rigid
Heng, Kevin [Institute for Astronomy, ETH Zuerich, Wolfgang-Pauli-Strasse 27, CH-8093 Zuerich (Switzerland)
Supersonic flows are expected to exist in the atmospheres of irradiated exoplanets, but the question of whether shocks develop lingers. Specifically, it reduces to whether continuous flow in a closed loop may become supersonic and if some portions of the supersonic flow steepen into shocks. We first demonstrate that continuous, supersonic flow may exist in two flavors: isentropic and non-isentropic, with shocks being included in the latter class of solutions. Supersonic flow is a necessary but insufficient condition for shocks to develop. The development of a shock requires the characteristics of neighboring points in a flow to intersect. We demonstrate that the intersection of characteristics may be quantified via the knowledge of the Mach number. Finally, we examine three-dimensional simulations of hot Jovian atmospheres and demonstrate that shock formation is expected to occur mostly on the dayside hemisphere, upstream of the substellar point, because the enhanced temperatures near the substellar point provide a natural pressure barrier for the returning flow. Understanding the role of shocks in irradiated exoplanetary atmospheres is relevant to correctly modeling observables such as the peak offsets of infrared phase curves.
Doctoral Programs Atmospheric, Oceanic & Space Sciences
Eustice, Ryan
University of Michigan Space Research Building 2455 Hayward Street Ann Arbor, MI 48109-2143 aoss Katherine E. White, Ann Arbor �The Regents of the University of Michigan Research areas Atmospheric Science Atmospheric Dynamics Climate, Climate Modeling & Climate Change Clouds & Precipitation Paleoclimate, Ice
Human effects on the global atmosphere
Johnston, H.S.
This review considers whether human activities can significantly change important functions of the global atmosphere by altering the amount or distribution of certain trace species. It deals with three specific topics: stratopheric ozone, the role of species other than carbon dioxide on the greenhouse effect, and certain recently recognized atmospheric consequences of a large scale nuclear war. 64 references, 10 figures, 2 tables.
ATMOSPHERIC SCIENCE LETTERS Atmos. Sci. Let. (2013)
Lee, Sukyoung
ATMOSPHERIC SCIENCE LETTERS Atmos. Sci. Let. (2013) Published online in Wiley Online Library Sciences, Seoul National University, Seoul, South Korea *Correspondence to: C. Yoo, Center for Atmosphere). A number of studies have shown that the MJO plays an important role in modulating the extratropical cir
ATOMIC IONIZATION AND OPACITIES IN PULSAR ATMOSPHERES Hydrogen Atmospheres J. VENTURA Physics.g. Pavlov et al., 1995; Zavlin et al., 1995, 1996; #12; 2 J. VENTURA ET AL. Rajagopal and Romani, 1996 the past three years. As is well known (Canuto and Ventura, 1977; Ruder et al., 1994), the external strong
Conditional data watchpoint management
Burdick, Dean Joseph (Austin, TX); Vaidyanathan, Basu (Austin, TX)
A method, system and computer program product for managing a conditional data watchpoint in a set of instructions being traced is shown in accordance with illustrative embodiments. In one particular embodiment, the method comprises initializing a conditional data watchpoint and determining the watchpoint has been encountered. Upon that determination, examining a current instruction context associated with the encountered watchpoint prior to completion of the current instruction execution, further determining a first action responsive to a positive context examination; otherwise, determining a second action.
Atmospheric neutrino flux calculation using the NRLMSISE00 atmospheric model
Honda, M; Kajita, T; Kasahara, K; Midorikawa, S
In this paper, we extend the calculation of the atmospheric neutrino flux~\\cite{hkkm2004,hkkms2006,hkkm2011} to the sites in polar and tropical regions. In our earliest full 3D-calculation~\\cite{hkkm2004}, we used DPMJET-III~\\cite{dpm} for the hadronic interaction model above 5~GeV, and NUCRIN~\\cite{nucrin} below 5~GeV. We modified DPMJET-III as in Ref.~\\cite{hkkms2006} to reproduce the experimental muon spectra better, mainly using the data observed by BESS group~\\cite{BESSTeVpHemu}. In a recent work~\\cite{hkkm2011}, we introduced JAM interaction model for the low energy hadronic interactions. JAM is a nuclear interaction model developed with PHITS (Particle and Heavy-Ion Transport code System)~\\cite{phits}. In Ref.~\\cite{hkkm2011}, we could reproduce the observed muon flux at the low energies at balloon altitude with DPMJET-III above 32 GeV and JAM below that better than the combination of DPMJET-III above 5~GeV and NUCRIN below that. Besides the interaction model, we have also improved the calculation sche...
Wakefield acceleration in atmospheric plasmas: a possible source of MeV electrons
Array�s, M; Seviour, R; Trueba, J L
Intense electromagnetic pulses interacting with a plasma can create a wake of plasma oscillations. Electrons trapped in such oscillations can be accelerated under certain conditions to very high energies. We study the conditions for the wakefield acceleration to produce MeV electrons in atmospheric plasmas. This mechanism may explain the origin of MeV or runaway electrons needed in the current theories for the production of Terrestrial Gamma ray Flashes.
Wind Energy-Related Atmospheric Boundary Layer Large-Eddy Simulation Using OpenFOAM: Preprint
Churchfield, M.J.; Vijayakumar, G.; Brasseur, J.G.; Moriarty, P.J.
This paper develops and evaluates the performance of a large-eddy simulation (LES) solver in computing the atmospheric boundary layer (ABL) over flat terrain under a variety of stability conditions, ranging from shear driven (neutral stratification) to moderately convective (unstable stratification).
Ris-PhD-Report Ecosystem-atmosphere exchange of carbon in
Ris�-PhD-Report Ecosystem-atmosphere exchange of carbon in a heathland under future climatic conditions Merete Bang Selsted Ris�-PhD-63(EN) July 2010 #12;Author: Merete Bang Selsted Title: Ecosystem environmental factors have separately and in combination effect on ecosystem processes. Terrestrial ecosystems
Physics 137, Section 1, Winter Semester Introduction to the Atmosphere and Weather
Hart, Gus
Physics 137, Section 1, Winter Semester Introduction to the Atmosphere and Weather OBSERVATIONAL observational project or present one TV-type weather forecast. A list of a few possible observational projects; weather conditions at times of observations, data tables, charts, sketches, graphs, descriptions of what
Radiative Transfer in the Midwave Infrared Applicable to Full Spectrum Atmospheric
Kerekes, John
of the radiative effects in the MWIR is needed. The MWIR is characterized by a unique combination of reduced solar conditions are stressing (e.g., high moisture, heavy aerosol/particulate loading, partial cloud cover, lowRadiative Transfer in the Midwave Infrared Applicable to Full Spectrum Atmospheric Characterization
Discrete magic angle turning system, apparatus, and process for in situ magnetic resonance spectroscopy and imaging
Hu, Jian Zhi (Richland, WA); Sears, Jr., Jesse A. (Kennewick, WA); Hoyt, David W. (Richland, WA); Wind, Robert A. (Kennewick, WA)
Described are a "Discrete Magic Angle Turning" (DMAT) system, devices, and processes that combine advantages of both magic angle turning (MAT) and magic angle hopping (MAH) suitable, e.g., for in situ magnetic resonance spectroscopy and/or imaging. In an exemplary system, device, and process, samples are rotated in a clockwise direction followed by an anticlockwise direction of exactly the same amount. Rotation proceeds through an angle that is typically greater than about 240 degrees but less than or equal to about 360 degrees at constant speed for a time applicable to the evolution dimension. Back and forth rotation can be synchronized and repeated with a special radio frequency (RF) pulse sequence to produce an isotropic-anisotropic shift 2D correlation spectrum. The design permits tubes to be inserted into the sample container without introducing plumbing interferences, further allowing control over such conditions as temperature, pressure, flow conditions, and feed compositions, thus permitting true in-situ investigations to be carried out.
Phase retrieval with the transport-of-intensity equation in an arbitrarily-shaped aperture by iterative discrete cosine transforms
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Huang, Lei; Zuo, Chao; Idir, Mourad; Qu, Weijuan; Asundi, Anand
A novel transport-of-intensity equation (TIE) based phase retrieval method is proposed with putting an arbitrarily-shaped aperture into the optical wavefield. In this arbitrarily-shaped aperture, the TIE can be solved under non-uniform illuminations and even non-homogeneous boundary conditions by iterative discrete cosine transforms with a phase compensation mechanism. Simulation with arbitrary phase, arbitrary aperture shape, and non-uniform intensity distribution verifies the effective compensation and high accuracy of the proposed method. Experiment is also carried out to check the feasibility of the proposed method in real measurement. Comparing to the existing methods, the proposed method is applicable for any types of phasemore��distribution under non-uniform illumination and non-homogeneous boundary conditions within an arbitrarily-shaped aperture, which enables the technique of TIE with hard aperture become a more flexible phase retrieval tool in practical measurements.��less
Sea ice loss and the changing atmospheric CO2 uptake capacity of the Arctic Ocean: Insights1 from the southeastern Canada Basin2
Paris-Sud XI, Universit� de
Sea ice loss and the changing atmospheric CO2 uptake capacity of the Arctic Ocean: Insights1 from (Arctic Ocean) to act as an atmospheric CO2 sink under the summertime ice-free conditions12 expected in the near future. Beneath a heavily decayed ice cover, we found surprisingly high13 pCO2sw (~290-320 atm
Further observations of a decreasing atmospheric CO2 uptake capacity in the Canada Basin (Arctic Ocean) due to sea ice loss
Boyer, Edmond
decayed ice cover, we found surprisingly high pCO2sw (~290�320 matm), considering that surface waterFurther observations of a decreasing atmospheric CO2 uptake capacity in the Canada Basin (Arctic as an atmospheric CO2 sink under the summertime ice-free conditions expected in the near future. Beneath a heavily
Distributed mean curvature on a discrete manifold for Regge calculus
Rory Conboye; Warner A. Miller; Shannon Ray
The integrated mean curvature of a simplicial manifold is well understood in both Regge Calculus and Discrete Differential Geometry. However, a well motivated pointwise definition of curvature requires a careful choice of volume over which to uniformly distribute the local integrated curvature. We show that hybrid cells formed using both the simplicial lattice and its circumcentric dual emerge as a remarkably natural structure for the distribution of this local integrated curvature. These hybrid cells form a complete tessellation of the simplicial manifold, contain a geometric orthonormal basis, and are also shown to give a pointwise mean curvature with a natural interpretation as a fractional rate of change of the normal vector.
Discrete Choice Analysis: Hydrogen FCV Demand Potential | Department of
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny:Revised Finding of No53197E T ADRAFT ENVIRONMENTAL ASSESSMENTEnergy Discrete
Technique to study corrosion in fluctuating gaseous atmospheres
Ficalora, P.J.; Godfrey, T.G.
The hot metal surfaces in a combustion system operating with an imperfect air-to-fuel mix experience a variation of corrosion potential. For example, the corrosion conditions can vary from reducing to oxidizing as the combustion conditions vary from rich to lean. This variation of conditions is particularly important in combustion systems utilizing sulfur-containing fuels since small variations in the sulfur partial pressure can cause catastrophic corrosion conditions. In an atmospheric fluidized-bed combustor (AFBC), coal is burned in the presence of a sulfur sorber, CaO or MgO. The alkaline oxide reacts with sulfur dioxide, the combustion product of the sulfur in the coal, to form the corresponding sulfate. Hence, the oxygen and sulfur dioxide partial pressures are controlled by the input conditions (air-coal ratio) as well as the sorption process. Figure 1 shows the observed variation of the oxygen partial pressure in an AFBC as a function of time and bed position. Clearly, fluctuations occur in a time interval of seconds, and the oxygen partial pressure can vary over approximately ten orders of magnitude. Corrosion in these fluctuating gaseous environments is being studied by measuring the resistance change of a heated metal filament specimen while it reacts with alternating oxidizing and sulfidizing gas pulses.
''Nuclear Winter'': A diagnosis of atmospheric general circulation model simulations
Covey, C.; Thompson, S.L.; Schneider, S.H.
We investigate the adiabatic and diabatic thermal balance of an atmospheric general circulation model (GCM) under two conditions: the control case, representing today's atmosphere, and a ''nuclear winter'' scenario in which virtually all sunlight in northern hemisphere and mid-latitudes is absorbed in the upper troposphere by prescribed dense smoke clouds hypothesized to result from the burning of many cities in a nuclear war. We also examine the changes in moisture and cloudiness simulated by the model. Our object is to examine the reliability of existing simulations of the climatic response to assumed dense, widespread, high-altitude smoke and to identify improvements needed in model parameterizations. We find that in the smoke-perturbed case our model simulation of land surface temperature is particularly influenced (i.e., warmed) by parameterized diffusion of heat downward from the lower troposphere. In turn the lower troposphere over land is supplied with heat transported from the relatively warm oceans. Thermal balance in the perturbed atmosphere as a whole is dominated by intense solar heating of the upper troposphere smoke layer in mid-latitudes balanced by parameterized dry convection and large-scale dynamical heat transport. Clouds largely disappear in the mid to upper troposphere in smoke-affected regions as a consequence of a decrease in local relative humidity that results from temperature increases and, to a smaller extent, from a reduction of vertical moisture transport. The computation of substantial downward vertical heat diffusion into the lowest model layer is almost certainly an overestimate for the smoke-perturbed conditions of high vertical stability.
The Upper Atmosphere of HD17156b
T. T. Koskinen; A. D. Aylward; S. Miller
HD17156b is a newly-found transiting extrasolar giant planet (EGP) that orbits its G-type host star in a highly eccentric orbit (e~0.67) with an orbital semi-major axis of 0.16 AU. Its period, 21.2 Earth days, is the longest among the known transiting planets. The atmosphere of the planet undergoes a 27-fold variation in stellar irradiation during each orbit, making it an interesting subject for atmospheric modelling. We have used a three-dimensional model of the upper atmosphere and ionosphere for extrasolar gas giants in order to simulate the progress of HD17156b along its eccentric orbit. Here we present the results of these simulations and discuss the stability, circulation, and composition in its upper atmosphere. Contrary to the well-known transiting planet HD209458b, we find that the atmosphere of HD17156b is unlikely to escape hydrodynamically at any point along the orbit, even if the upper atmosphere is almost entirely composed of atomic hydrogen and H+, and infrared cooling by H3+ ions is negligible. The nature of the upper atmosphere is sensitive to to the composition of the thermosphere, and in particular to the mixing ratio of H2, as the availability of H2 regulates radiative cooling. In light of different simulations we make specific predictions about the thermosphere-ionosphere system of HD17156b that can potentially be verified by observations.
Mass spectrometric approaches for chemical characterisation of atmospheric aerosols: critical
Nizkorodov, Sergey
Mass spectrometric approaches for chemical characterisation of atmospheric aerosols: critical. Atmospheric aerosols have profound effects on the environment through several physicochemical processes on the respiratory and cardiovascular systems. Understanding aerosol atmospheric chemistry and its environmental
Mineralogy under extreme conditions
Shu, Jinfu (CIW)
We have performed measurements of minerals based on the synchrotron source for single crystal and powder X-ray diffraction, inelastic scattering, spectroscopy and radiography by using diamond anvil cells. We investigated the properties of iron (Fe), iron-magnesium oxides (Fe, Mg)O, silica(SiO{sub 2}), iron-magnesium silicates (Fe, Mg)SiO{sub 3} under simulated high pressure-high temperature extreme conditions of the Earth's crust, upper mantle, low mantle, core-mantle boundary, outer core, and inner core. The results provide a new window on the investigation of the mineral properties at Earth's conditions.
Precision Determination of Atmospheric Extinction at Optical and Near IR Wavelengths
Burke, David L.; /SLAC; Axelrod, T.; /Arizona U., Astron. Dept. - Steward Observ.; Blondin, Stephane; /European Southern Observ. /Marseille, CPPM; Claver, Chuck; /NOAO, Tucson; Ivezic, Zeljko; Jones, Lynne; /Washington U., Seattle, Astron. Dept.; Saha, Abhijit; /NOAO, Tucson; Smith, Allyn; /Austin Peay State U.; Smith, R.Chris; /Cerro-Tololo InterAmerican Obs.; Stubbs, Christopher W.; /Harvard-Smithsonian Ctr. Astrophys.
The science goals for future ground-based all-sky surveys, such as the Dark Energy Survey, PanSTARRS, and the Large Synoptic Survey Telescope, require calibration of broadband photometry that is stable in time and uniform over the sky to precisions of a per cent or better, and absolute calibration of color measurements that are similarly accurate. This performance will need to be achieved with measurements made from multiple images taken over the course of many years, and these surveys will observe in less than ideal conditions. This paper describes a technique to implement a new strategy to directly measure variations of atmospheric transmittance at optical wavelengths and application of these measurements to calibration of ground-based observations. This strategy makes use of measurements of the spectra of a small catalog of bright 'probe' stars as they progress across the sky and back-light the atmosphere. The signatures of optical absorption by different atmospheric constituents are recognized in these spectra by their characteristic dependences on wavelength and airmass. State-of-the-art models of atmospheric radiation transport and modern codes are used to accurately compute atmospheric extinction over a wide range of observing conditions. We present results of an observing campaign that demonstrate that correction for extinction due to molecular constituents and aerosols can be done with precisions of a few millimagnitudes with this technique.
all-atom discrete molecular: Topics by E-print Network
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recurrence satisfied by the Stirling numbers of the second kind. Abrams, Aaron; Hower, Valerie 2010-01-01 244 VARIATIONAL ESTIMATES FOR DISCRETE SCHR Mathematics Websites...
Taming the Curse of Dimensionality: Discrete Integration by Hashing and Optimization
Bejerano, Gill
Taming the Curse of Dimensionality: Discrete Integration by Hashing and Optimization Stefano Ermon but without a tightness guarantee. Markov Chain Monte Carlo (MCMC) methods for sampling are asymptotically
Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle material
Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle are derived either at microscale with random distribution of material properties or at a mesoscale
Dual hidden landscapes in Anderson localization on discrete lattices
Marcelo Leite Lyra; Svitlana Mayboroda; Marcel Filoche
The localization subregions of stationary waves in continuous disordered media have been recently demonstrated to be governed by a hidden landscape that is the solution of a Dirichlet problem expressed with the wave operator. In this theory, the strength of Anderson localization confinement is determined by this landscape, and continuously decreases as the energy increases. However, this picture has to be changed in discrete lattices in which the eigenmodes close to the edge of the first Brillouin zone are as localized as the low energy ones. Here we show that in a 1D discrete lattice, the localization of low and high energy modes is governed by two different landscapes, the high energy landscape being the solution of a dual Dirichlet problem deduced from the low energy one using the symmetries of the Hamiltonian. We illustrate this feature using the one-dimensional tight-binding Hamiltonian with random on-site potentials as a prototype model. Moreover we show that, besides unveiling the subregions of Anderson localization, these dual landscapes also provide an accurate overal estimate of the localization length over the energy spectrum, especially in the weak disorder regime.
A Method for Treating Discretization Error in Nondeterministic Analysis
Alvin, K.F.
A response surface methodology-based technique is presented for treating discretization error in non-deterministic analysis. The response surface, or metamodel, is estimated from computer experiments which vary both uncertain physical parameters and the fidelity of the computational mesh. The resultant metamodel is then used to propagate the variabilities in the continuous input parameters, while the mesh size is taken to zero, its asymptotic limit. With respect to mesh size, the metamodel is equivalent to Richardson extrapolation, in which solutions on coarser and finer meshes are used to estimate discretization error. The method is demonstrated on a one dimensional prismatic bar, in which uncertainty in the third vibration frequency is estimated by propagating variations in material modulus, density, and bar length. The results demonstrate the efficiency of the method for combining non-deterministic analysis with error estimation to obtain estimates of total simulation uncertainty. The results also show the relative sensitivity of failure estimates to solution bias errors in a reliability analysis, particularly when the physical variability of the system is low.
Atmospheric science encompasses meteorology and climatology, as well as fields such as atmospheric chemistry and remote sensing.Atmospheric
Oceanography and Meteorology Building.The Doppler weather radar on the roof of the building is a campus Mobile Atmospheric Research and Teaching Radar (SMART-R).This radar is used in national and international
A Convective-like Energy-Stable Open Boundary Condition for Simulations of Incompressible Flows
Dong, Suchuan
We present a new energy-stable open boundary condition, and an associated numerical algorithm, for simulating incompressible flows with outflow/open boundaries. This open boundary condition ensures the energy stability of the system, even when strong vortices or backflows occur at the outflow boundary. Under certain situations it can be reduced to a form that can be analogized to the usual convective boundary condition. One prominent feature of this boundary condition is that it provides a control over the velocity on the outflow/open boundary. This is not available with the other energy-stable open boundary conditions from previous works. Our numerical algorithm treats the proposed open boundary condition based on a rotational velocity-correction type strategy. It gives rise to a Robin-type condition for the discrete pressure and a Robin-type condition for the discrete velocity on the outflow/open boundary, respectively at the pressure and the velocity sub-steps. We present extensive numerical experiments on...
2300 SYSTEM Conditioning Amplifier
Gellman, Andrew J.
2300 SYSTEM Signal Conditioning Amplifier 2310 Instruction Manual Vishay Micro-Measurements P date of shipment. Coverage of computers, cameras, rechargeable batteries, and similar items, sold on non-rechargeable batteries and similar consumable items is limited to the delivery of goods free from
Pulsed atmospheric fluidized bed combustion
Not Available
In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were established experimentally. A considerable amount of the effort was invested in the initial task of constructing an AFBC that would represent a reasonable baseline against which the performance of the PAFBC could be compared. A summary comparison of the performance and emissions data from the MTCI 2 ft {times} 2 ft facility (AFBC and PAFBC modes) with those from conventional BFBC (taller freeboard and recycle operation) and circulating fluidized bed combustion (CFBC) units is given in Table ES-1. The comparison is for typical high-volatile bituminous coals and sorbents of average reactivity. The values indicated for BFBC and CFBC were based on published information. The AFBC unit that was designed to act as a baseline for the comparison was indeed representative of the larger units even at the smaller scale for which it was designed. The PAFBC mode exhibited superior performance in relation to the AFBC mode. The higher combustion efficiency translates into reduced coal consumption and lower system operating cost; the improvement in sulfur capture implies less sorbent requirement and waste generation and in turn lower operating cost; lower NO{sub x} and CO emissions mean ease of site permitting; and greater steam-generation rate translates into less heat exchange surface area and reduced capital cost. Also, the PAFBC performance generally surpasses those of conventional BFBC, is comparable to CFBC in combustion and NO{sub x} emissions, and is better than CFBC in sulfur capture and CO emissions even at the scaled-down size used for the experimental feasibility tests.
atmospheric pressure ionization: Topics by E-print Network
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for Atmospheric Pressure, in Vivo, and Imaging Mass. For example, atmospheric pressure infrared MALDI (AP IR-MALDI), capable of producing ions from small ionization (DESI),5...
atmospheric carbon emissions: Topics by E-print Network
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oxide (N2O) 13 Paris-Sud XI, Universit de 13 Atmospheric Lifetime of Fossil Fuel Carbon Dioxide Geosciences Websites Summary: Atmospheric Lifetime of Fossil Fuel Carbon...
atmospheric oxygenation recorded: Topics by E-print Network
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cores may contain high quality records of atmospheric deposition. The qualitative Short, Daniel 3 Bistability of atmospheric oxygen and the Great Oxidation Geosciences Websites...
atmospheric optical turbulence: Topics by E-print Network
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Next Page Last Page Topic Index 1 Atmospheric Turbulence and its Influence on Adaptive Optics Physics Websites Summary: Atmospheric Turbulence and its Influence on Adaptive Optics...
atmospheric ion measurements: Topics by E-print Network
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the Atmospheric CERN Preprints Summary: We report the first observation in a high energy neutrino telescope of cascades induced by atmospheric electron neutrinos and by...
Comparative Analysis of Urban Atmospheric Aerosol by Particle...
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Analysis of Urban Atmospheric Aerosol by Particle-Induced X-ray Emission (PIXE), Proton Elastic Scattering Analysis Comparative Analysis of Urban Atmospheric Aerosol by...
Atmospheric Solids Analysis Probe Mass Spectrometry: A New Approach...
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Atmospheric Solids Analysis Probe Mass Spectrometry: A New Approach for Airborne Particle Analysis. Atmospheric Solids Analysis Probe Mass Spectrometry: A New Approach for Airborne...
A Volcanologist'S Review Of Atmospheric Hazards Of Volcanic Activity...
atmospheric hazards caused by explosive volcanic activity. The hazard posed by fine silicate ash with long residence time in the atmosphere is probably much less serious than...
Diesel and Gasoline Engine Emissions: Characterization of Atmosphere...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Characterization of Atmosphere Composition and Health Responses to Inhaled Emissions Diesel and Gasoline Engine Emissions: Characterization of Atmosphere Composition and Health...
Fehner and Gosling, Atmospheric Nuclear Weapons Testing, 1951...
Atmospheric Nuclear Weapons Testing, 1951-1963. Battlefield of the Cold War: The Nevada Test Site, Volume I Fehner and Gosling, Atmospheric Nuclear Weapons Testing, 1951-1963....
atmospheric global electric: Topics by E-print Network
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global atmospheric iron cycle, and combustion this paper. Key Words aerosol deposition, climate change, deserts Abstract Atmospheric inputs of iron sources of iron are...
atmospheric dispersion coefficient: Topics by E-print Network
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the earth surface. In general, the atmospheric motion is driven by the intense solar energy arriving at the equator 3 A GIS-based atmospheric dispersion model Computer...
atmospheric dispersion calculations: Topics by E-print Network
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the earth surface. In general, the atmospheric motion is driven by the intense solar energy arriving at the equator 4 A GIS-based atmospheric dispersion model Computer...
atmospheric dispersion experiment: Topics by E-print Network
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the earth surface. In general, the atmospheric motion is driven by the intense solar energy arriving at the equator 2 A GIS-based atmospheric dispersion model Computer...
atmospheric climate model: Topics by E-print Network
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Curry & Webster Atmospheric Thermodynamics Ch1 Composition Ch2 Laws Ch3 Transfers Ch12 Energy Russell, Lynn 10 Climate Sciences: Atmospheric Thermodynamics Environmental...
atmosphere box model: Topics by E-print Network
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GloveBoxes Glove boxes allow the user to perform operations in an atmosphere 8 University Corporation for Atmospheric Research PO Box 3000 Boulder, Colorado 80307 Geosciences...
Oxygen detected in atmosphere of Saturn's moon Dione
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Oxygen detected in atmosphere of Saturn's moon Dione Oxygen detected in atmosphere of Saturn's moon Dione Scientists and an international research team have announced discovery of...
atmospheric modeling system: Topics by E-print Network
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14 Causes and implications of persistent atmospheric carbon dioxide biases in Earth System Models University of California eScholarship Repository Summary: Atmosphere and Ocean...
atmospheric co2 content: Topics by E-print Network
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Of Physics Version 4 Gerlich and Ralf D. Tscheuschner Abstract The atmospheric greenhouse effect, an idea that many authors Of The Atmospheric CO2 Greenhouse Effects . . . 3...
atmospheric chemistry simulations: Topics by E-print Network
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Environmental Sciences and Ecology Websites Summary: , nitrogen and oxygen The Greenhouse Effect Atmospheric Aerosols Atmospheric chemical kinetics including and oral reports to...
atmospheric sciences exposure: Topics by E-print Network
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annual reviews of faculty performance in accordance 8 Space Science : Atmosphere Greenhouse Effect Physics Websites Summary: Space Science : Atmosphere Greenhouse Effect Part-5a...
atmospheric chemistry project: Topics by E-print Network
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Environmental Sciences and Ecology Websites Summary: , nitrogen and oxygen The Greenhouse Effect Atmospheric Aerosols Atmospheric chemical kinetics including and oral reports to...
atmospheric co2 concentrations: Topics by E-print Network
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Of Physics Version 4 Gerlich and Ralf D. Tscheuschner Abstract The atmospheric greenhouse effect, an idea that many authors Of The Atmospheric CO2 Greenhouse Effects . . . 3...
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Of Physics Version 4 Gerlich and Ralf D. Tscheuschner Abstract The atmospheric greenhouse effect, an idea that many authors Of The Atmospheric CO2 Greenhouse Effects . . . 3...
atmospheric co2 laser: Topics by E-print Network
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Of Physics Version 4 Gerlich and Ralf D. Tscheuschner Abstract The atmospheric greenhouse effect, an idea that many authors Of The Atmospheric CO2 Greenhouse Effects . . . 3...
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large solar proton Paris-Sud XI, Universit de 7 Space Science : Atmosphere Greenhouse Effect Physics Websites Summary: Space Science : Atmosphere Greenhouse Effect Part-5a...
atmospheric chemistry programme: Topics by E-print Network
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Environmental Sciences and Ecology Websites Summary: , nitrogen and oxygen The Greenhouse Effect Atmospheric Aerosols Atmospheric chemical kinetics including and oral reports to...
atmospheric co2 measurements: Topics by E-print Network
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Of Physics Version 4 Gerlich and Ralf D. Tscheuschner Abstract The atmospheric greenhouse effect, an idea that many authors Of The Atmospheric CO2 Greenhouse Effects . . . 3...
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Of Physics Version 4 Gerlich and Ralf D. Tscheuschner Abstract The atmospheric greenhouse effect, an idea that many authors Of The Atmospheric CO2 Greenhouse Effects . . . 3...
atmospheric chemistry experiment: Topics by E-print Network
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Environmental Sciences and Ecology Websites Summary: , nitrogen and oxygen The Greenhouse Effect Atmospheric Aerosols Atmospheric chemical kinetics including and oral reports to...
atmospheric science people: Topics by E-print Network
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annual reviews of faculty performance in accordance 9 Space Science : Atmosphere Greenhouse Effect Physics Websites Summary: Space Science : Atmosphere Greenhouse Effect Part-5a...
atmospheric chemistry: Topics by E-print Network
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Environmental Sciences and Ecology Websites Summary: , nitrogen and oxygen The Greenhouse Effect Atmospheric Aerosols Atmospheric chemical kinetics including and oral reports to...
atmospheric sciences: Topics by E-print Network
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annual reviews of faculty performance in accordance 8 Space Science : Atmosphere Greenhouse Effect Physics Websites Summary: Space Science : Atmosphere Greenhouse Effect Part-5a...
atmospheric co2 mixing: Topics by E-print Network
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Of Physics Version 4 Gerlich and Ralf D. Tscheuschner Abstract The atmospheric greenhouse effect, an idea that many authors Of The Atmospheric CO2 Greenhouse Effects . . . 3...
atmospheric aerosols basic: Topics by E-print Network
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of atmospheric aerosol. Aplin, KL 2012-01-01 13 1. Introduction The atmospheric greenhouse effect is the basic mechanism Environmental Sciences and Ecology Websites Summary: 1....
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Mercury in the Global Atmosphere: Chemistry, deposition, and land-atmosphere interactions Environmental Management and Restoration Websites Summary: Mercury in the Global...
atmospheric deposition nutrient: Topics by E-print Network
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Mercury in the Global Atmosphere: Chemistry, deposition, and land-atmosphere interactions Environmental Management and Restoration Websites Summary: Mercury in the Global...
Visualizing Storms from NCAR's Atmosphere Model at NERSC
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Atmosphere Model Visualizing Storms from NCAR's Atmosphere Model CCSM-sprabhat.png Global warming will likely change the statistics of tropical cyclones and hurricanes. In this...
Necessary conditions for stabilization agreements
Yang, Zili.; Jacoby, Henry D.
The Climate Convention calls for stabilization of atmospheric concentrations of greenhouse gases. This paper considers the issues that must be faced in formulating a plan to meet any such target, using a proposed CO2 level ...
Near Maximal Atmospheric Neutrino Mixing in Neutrino Mass Models with Two Texture Zeros
S. Dev; Radha Raman Gautam; Lal Singh; Manmohan Gupta
The implications of a large value of the effective Majorana neutrino mass for a class of two texture zero neutrino mass matrices have been studied in the flavor basis. It is found that these textures predict near maximal atmospheric neutrino mixing angle in the limit of large effective Majorana neutrino mass. It is noted that this prediction is independent of the values of solar and reactor neutrino mixing angles. We present the symmetry realization of these textures using the discrete cyclic group $Z_3$. It is found that the texture zeros realised in this work remain stable under renormalization group running of the neutrino mass matrix from the seesaw scale to the electroweak scale, at one loop level.
Fish Passage though Hydropower Turbines: Simulating Blade Strike using the Discrete Element Method
Richmond, Marshall C.; Romero Gomez, Pedro DJ
mong the hazardous hydraulic conditions affecting anadromous and resident fish during their passage though turbine flows, two are believed to cause considerable injury and mortality: collision on moving blades and decompression. Several methods are currently available to evaluate these stressors in installed turbines, i.e. using live fish or autonomous sensor devices, and in reduced-scale physical models, i.e. registering collisions from plastic beads. However, a priori estimates with computational modeling approaches applied early in the process of turbine design can facilitate the development of fish-friendly turbines. In the present study, we evaluated the frequency of blade strike and nadir pressure environment by modeling potential fish trajectories with the Discrete Element Method (DEM) applied to fish-like composite particles. In the DEM approach, particles are subjected to realistic hydraulic conditions simulated with computational fluid dynamics (CFD), and particle-structure interactions�representing fish collisions with turbine blades�are explicitly recorded and accounted for in the calculation of particle trajectories. We conducted transient CFD simulations by setting the runner in motion and allowing for better turbulence resolution, a modeling improvement over the conventional practice of simulating the system in steady state which was also done here. While both schemes yielded comparable bulk hydraulic performance, transient conditions exhibited a visual improvement in describing flow variability. We released streamtraces (steady flow solution) and DEM particles (transient solution) at the same location from where sensor fish (SF) have been released in field studies of the modeled turbine unit. The streamtrace-based results showed a better agreement with SF data than the DEM-based nadir pressures did because the former accounted for the turbulent dispersion at the intake but the latter did not. However, the DEM-based strike frequency is more representative of blade-strike probability than the steady solution is, mainly because DEM particles accounted for the full fish length, thus resolving (instead of modeling) the collision event.
Adaptive control for Mars atmospheric flight
Restrepo, Carolina Isabel
landing accuracy requirements for a manned space vehicle make it necessary to ?y a controlled entry trajectory rather than a more robust ballistic entry trajectory used for some robotic missions. The large variations in Mars atmospheric properties make a...
Composition and Reactions of Atmospheric Aerosol Particles
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large portion of the microscopic particles floating in the air originate from incomplete combustion of coal and oil and from dust storms. Once in the atmosphere, they can have...
The porous atmosphere of eta Carinae
Nir J. Shaviv
We analyze the wind generated by the great 20 year long super-Eddington outburst of eta-Carinae. We show that using classical stellar atmospheres and winds theory, it is impossible to construct a consistent wind model in which a sufficiently small amount of mass, like the one observed, is shed. One expects the super-Eddington luminosity to drive a thick wind with a mass loss rate substantially higher than the observed one. The easiest way to resolve the inconsistency is if we alleviate the implicit notion that atmospheres are homogeneous. An inhomogeneous atmosphere, or "porous", allows more radiation to escape while exerting a smaller average force. Consequently, such an atmosphere yields a considerably lower mass loss rate for the same total luminosity. Moreover, all the applications of the Eddington Luminosity as a strict luminosity limit should be revised, or at least reanalyzed carefully.
Space Science: Atmospheres Evolution of planets
Johnson, Robert E.
;Atmospheres / Evolution Heat Sources Compressional Energy Trapped Radioactive Material Tidal Interactions, same A) the surface temperature,Tg, increases. WOW! Simple #12;Temperature vs. time in an Early Epoch
MIDDLE ATMOSPHERE DYNAMICS AT707 (3 credits)
., Holton, J. R., Leovy, C. B., Academic Press, 489 pp. · Atmospheric and Oceanic Fluid Dynamics, 2006 Review Articles: · Haynes, P. H., 2005: Stratospheric Dynamics. Annu. Rev. Fluid Mech., 37, 263 293
Lookup tables to compute high energy cosmic ray induced atmospheric ionization and changes in atmospheric chemistry
Dimitra Atri; Adrian L. Melott; Brian C. Thomas
A variety of events such as gamma-ray bursts and supernovae may expose the Earth to an increased flux of high-energy cosmic rays, with potentially important effects on the biosphere. Existing atmospheric chemistry software does not have the capability of incorporating the effects of substantial cosmic ray flux above 10 GeV . An atmospheric code, the NASA-Goddard Space Flight Center two-dimensional (latitude, altitude) time-dependent atmospheric model (NGSFC), is used to study atmospheric chemistry changes. Using CORSIKA, we have created tables that can be used to compute high energy cosmic ray (10 GeV - 1 PeV) induced atmospheric ionization and also, with the use of the NGSFC code, can be used to simulate the resulting atmospheric chemistry changes. We discuss the tables, their uses, weaknesses, and strengths.
Simulation of Aerosol Behavior in a Saturated Atmosphere With the CONTAIN Code
Kljenak, Ivo; Mavko, Borut [Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia)
Experiments on aerosol behavior in an atmosphere containing saturated vapor, which were performed in the KAEVER experimental facility and proposed for the OECD International Standard Problem No. 44, were simulated with the CONTAIN thermal-hydraulic computer code. The purpose of the work was to assess the capability of the CONTAIN code to model aerosol condensation and deposition in a containment of a light-water-reactor nuclear power plant at severe accident conditions. Results of dry and wet aerosol concentrations in the test vessel atmosphere are presented and analyzed. (authors)
Air Activation Following an Atmospheric Explosion
Lowrey, Justin D.; McIntyre, Justin I.; Prichard, Andrew W.; Gesh, Christopher J.
In addition to thermal radiation and fission products, nuclear explosions result in a very high flux of unfissioned neutrons. Within an atmospheric nuclear explosion, these neutrons can activate the various elemental components of natural air, potentially adding to the radioactive signature of the event as a whole. The goal of this work is to make an order-of-magnitude estimate of the total amount of air activation products that can result from an atmospheric nuclear explosion.
Trace analysis of atmospheric organic bases
Clark, Dwayne C.
chromatographic fractions for NS analyses ( 121) and its use as a thin layer chromatography (TLC) adsorbent ( 122). The National Institute of Occupational Safety and Health (NIOSH) recommends its use in the analysis of many industrial vapors ( 113 - 120... analysis of atmospheric organic bases were investigated; the study included (1) the analysis of submarine charcoal filter bed samples for nitrogen bases and (2) the use of metallic tetraphenylporphines (TPP) as specific adsorbents for atmospheric...
Quantum light in the turbulent atmosphere
A. A. Semenov; W. Vogel
Nonclassical properties of light propagating through the turbulent atmosphere are studied. We demonstrate by numerical simulation that the probability distribution of the transmission coefficient, which characterizes the effects of the atmosphere on the quantum state of light, can be reconstructed by homodyne detection. Nonclassical photon-statistics and, more generally, nonclassical Glauber-Sudarshan functions appear to be more robust against turbulence for weak light fields rather than for bright ones.
Atmospheric State, Cloud Microphysics and Radiative Flux
DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]
Mace, Gerald
Atmospheric thermodynamics, cloud properties, radiative fluxes and radiative heating rates for the ARM Southern Great Plains (SGP) site. The data represent a characterization of the physical state of the atmospheric column compiled on a five-minute temporal and 90m vertical grid. Sources for this information include raw measurements, cloud property and radiative retrievals, retrievals and derived variables from other third-party sources, and radiative calculations using the derived quantities.
High voltage pulse conditioning
Springfield, Ray M. (Sante Fe, NM); Wheat, Jr., Robert M. (Los Alamos, NM)
Apparatus for conditioning high voltage pulses from particle accelerators in order to shorten the rise times of the pulses. Flashover switches in the cathode stalk of the transmission line hold off conduction for a determinable period of time, reflecting the early portion of the pulses. Diodes upstream of the switches divert energy into the magnetic and electrostatic storage of the capacitance and inductance inherent to the transmission line until the switches close.
Lokhandwala, Kaaeid A. (Union City, CA)
A process for conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas, so that it can be used as combustion fuel to run gas-powered equipment, including compressors, in the gas field or the gas processing plant. Compared with prior art processes, the invention creates lesser quantities of low-pressure gas per unit volume of fuel gas produced. Optionally, the process can also produce an NGL product.
An investigation of the atmospheric physical conditions associated with microwave propagation
Riggs, Lowell Pogue
wm 1000ed fer this periods oooarriag deria0 the cise ef the freatsl pass s0e The wiads wore aet fawsrshle fot' Ap fsrastioa swd it is thoa0ht that. ths presaaoo of dissiyatiag chaaderstoras wich tho frsacsl yass- sgo scold have hoes tha priowry... eaaepc chat the tsp ef the ~Cetera Layer was abase 3000 feet sa4 ia tha pasC fe?ease st?4ias this had bess ~ 4sterrest ts Ap forostim. Appsreatly, Che 1001 swr- fase relative h@a14icy wss streag oaosgh Co fera s ~istwro gra4iesC with the evsrmLL valse...
Design and construction of uniform glow discharge plasma system operating under atmospheric condition
Kocum, C.; Ayhan, H. [Biomedical Engineering Department, Baskent University, Ankara 06530 (Turkey); Chemistry Department, Biochemistry Division, Mugla University, Faculty of Science, Koetekli, 48170 Mugla (Turkey)
The design of a uniform glow discharge plasma system operating without vacuum is presented. A full-bridge switching circuit was used to switch the transformers. The primary windings of transformers were connected in parallel, but in opposite phase to double the output voltage. Theoretically, 20 000 V{sub pp} was obtained. Rectangle copper electrodes were used, and placed parallel to each other. To prevent the spark production that is, to obtain uniformity, two 2 mm Teflon sheets were glued to the electrodes. However, it was observed that the operating frequency also affected the uniformity. For the system presented here, the frequency at which more uniformity was obtained was found to be 14 kHz.
Leaf water potential in Pinus taeda L. as related to fluctuating soil water and atmospheric conditions
Ellison, Stanley Lee
growing on Bienville loamy fine sand near Rusk, Texas. The average available water storage capacity was 9. 50 inches in the 8-foot profile. Siruiltaneous measurements of leaf water potential and environmental variables were made weekly at two hour... pressure 2 deficit, temperature, and wind (R 0. 78). A regression equation relating total daily water stress to only vapor pressure deficit and soil water content in the 0- to 4-foot soil layer was also signifi- 2= cant (R = 0. 76). The total daily...
Multipole-preserving quadratures for discretization of functions
Genovese, Luigi
Discretizing an analytic function on a uniform real-space grid is often done via a straightforward collocation method. This is ubiquitous in all areas of computational physics and quantum chemistry. An example in Density Functional Theory is given by the local external potential describing the interaction between ions and electrons. Also notable examples are given by the analytic functions defining compensation charges for range-separated electrostatic treatments. The accuracy of the collocation method used is therefore very important for the reliability of subsequent treatments like self-consistent field solutions of the electronic structure problems. When the real-space grid is too coarse, the collocation method introduces numerical artifacts typical of real-space treatments, like the so-called egg-box error, that may spoil the numerical stability of the description. We present in this paper a new quadrature scheme that is able to exactly preserve the multipoles of a given analytic function for a wide range...
Breaking discrete symmetries in the effective field theory of inflation
Dario Cannone; Jinn-Ouk Gong; Gianmassimo Tasinato
We study the phenomenon of discrete symmetry breaking during the inflationary epoch, using a model-independent approach based on the effective field theory of inflation. We work in a context where both time reparameterization symmetry and spatial diffeomorphism invariance can be broken during inflation. We determine the leading derivative operators in the quadratic action for fluctuations that break parity and time-reversal. Within suitable approximations, we study their consequences for the dynamics of linearized fluctuations. Both in the scalar and tensor sectors, we show that such operators can lead to new direction-dependent phases for the modes involved. They do not affect the power spectra, but can have consequences for higher correlation functions. Moreover, a small quadrupole contribution to the sound speed can be generated.
Sampling Theorem and Discrete Fourier Transform on the Riemann Sphere
Manuel Calixto; Julio Guerrero; Juan Carlos S�nchez-Monreal
Using coherent-state techniques, we prove a sampling theorem for Majorana's (holomorphic) functions on the Riemann sphere and we provide an exact reconstruction formula as a convolution product of $N$ samples and a given reconstruction kernel (a sinc-type function). We also discuss the effect of over- and under-sampling. Sample points are roots of unity, a fact which allows explicit inversion formulas for resolution and overlapping kernel operators through the theory of Circulant Matrices and Rectangular Fourier Matrices. The case of band-limited functions on the Riemann sphere, with spins up to $J$, is also considered. The connection with the standard Euler angle picture, in terms of spherical harmonics, is established through a discrete Bargmann transform.
Public key Steganography Using Discrete Cross-Coupled Chaotic Maps
Sodeif Ahadpour; Mahdiyeh Majidpour; Yaser Sadra
By cross-coupling two logistic maps a novel method is proposed for the public key steganography in JPEG image. Chaotic maps entail high complexity in the used algorithm for embedding secret data in a medium. In this paper, discrete cross- coupled chaotic maps are used to specifying the location of the different parts of the secret data in the image. Modifying JPEG format during compressing and decompressing, and also using public key enhanced difficulty of the algorithm. Simulation results show that in addition to excessive capacity, this method has high robustness and resistance against hackers and can be applicable in secret communication. Also the PSNR value is high compared to the other works.
Lazy learning indirect control for discrete-time non-linear systems Gianluca Bontempi, Mauro Birattari
Bontempi, Gianluca
Lazy learning indirect control for discrete-time non-linear systems Gianluca Bontempi, Mauro propose a hybrid architecture for the indirect control of non linear discrete time plants from of the resulting controller in a simplified case. Experimental results in the control of some non linear benchmarks
Offset-free control of constrained linear discrete-time systems subject to persistent
Cambridge, University of
Offset-free control of constrained linear discrete-time systems subject to persistent unmeasured-free control of constrained linear discrete-time systems subject to persistent unmeasured disturbances Gabriele Technical report CUED/F-INFENG/TR.466 September 10, 2003 #12;#12;Offset-free control of constrained linear
Friction dependence of shallow granular flows from discrete par-ticle simulations
Al Hanbali, Ahmad
Friction dependence of shallow granular flows from discrete par- ticle simulations Anthony Thornton relation for the macroscopic bed friction or basal roughness obtained from micro-scale discrete particle simulations of steady flows. We systematically vary the bed friction by changing the contact friction
Recursive Total Least Squares: An Alternative to the Discrete Kalman Filter
Boley, Daniel
Recursive Total Least Squares: An Alternative to the Discrete Kalman Filter Daniel L. Boley The discrete Kalman lter, which is becoming a common tool for reducing uncertainty in robot navigation, su ers total least squares estimator (RTLS) as an alternative to the Kalman lter, and compare
Various ways to compute the continuous-discrete Extended Kalman Filter
Paris-Sud XI, Universit� de
1 Various ways to compute the continuous-discrete Extended Kalman Filter Paul Frogerais, Jean-Jacques Bellanger and Lotfi Senhadji Abstract--The Extended Kalman Filter (EKF) is a very popular tool dealing is guaranteed. Index Terms--Extended Kalman filters, Continuous- discrete filters, Runge-Kutta method, nonlinear
Recursive Total Least Squares: An Alternative to Using the Discrete Kalman
Boley, Daniel
Recursive Total Least Squares: An Alternative to Using the Discrete Kalman Filter in Robot to ob- tain the best estimate of the robot position. The discrete Kalman filter, com- monly used the Kalman filter. To this end, we propose the use of a Recursive Total Least Squares Filter. This filter
To appear in Journal of Computational Physics Parallel Discrete Molecular Dynamics Simulation
Herbordt, Martin
To appear in Journal of Computational Physics Parallel Discrete Molecular Dynamics Simulation and Automated Design Laboratory Department of Electrical and Computer Engineering Boston University; Boston, MA 02215 www.bu.edu/caadlab; email: email@example.com, email@example.com Abstract: Discrete molecular dynamics
Optimal Supervisory Control of Discrete Event Dynamical Systems 1,2
Kumar, Ratnesh
Optimal Supervisory Control of Discrete Event Dynamical Systems 1,2 Ratnesh Kumar Department;Abstract We formalize the notion of optimal supervisory control of discrete event dynamical sys- tems (DEDS some undesired states, or not reaching some desired states in the controlled system. The control
On Optimal Control of a Class of Partially-Observed Discrete Event Systems
Paris-Sud XI, Universit� de
On Optimal Control of a Class of Partially-Observed Discrete Event Systems H e rv M a rch a n d theC-observer. Thissubmachineleadstothedesiredsupervisorforthesystem. Keywords: DiscreteEventSystems,SupervisoryControlProblem,Optimality(not) be reached in the controlled system, the Optimal Control under Par- tial Observation problem is solved
Boyer, Edmond
of the plant with a timed discrete model of the controller. We will also show, using a basic examplePERFORMANCE VERIFICATION OF DISCRETE EVENT SYSTEMS USING HYBRID MODEL-CHECKING Bruno Denis (1 Systems (DES) and Hybrid Dynamic Systems (HDS) are quite substantial, especially as regards the controller
Propagation failure in the discrete Nagumo equation H. J. Hupkes a,, D. Pelinovsky b
Hupkes, Hermen Jan
Propagation failure in the discrete Nagumo equation H. J. Hupkes a,, D. Pelinovsky b , B. Sandstede Email: email@example.com b Department of Mathematics - McMaster University Hamilton, ON L8S 4K1 problem of propagation failure for monotonic fronts of the discrete Nagumo equation. For a special class
Maggioni, Mauro
WAVELET FRAMES ON GROUPS AND HYPERGROUPS VIA DISCRETIZATION OF CALDER´ON FORMULAS MAURO MAGGIONI Abstract. Continuous wavelets are often studied in the general framework of representation theory of square whether these continuous wavelets can be discretized to yield wavelet frames. In this paper we us Calder
The Discrete Wavelet Transform in S G. P. Nason \\Lambda and B. W. Silverman y
Nason, Guy
The Discrete Wavelet Transform in S G. P. Nason \\Lambda and B. W. Silverman y Journal of Computational and Graphical Statistics (1994) 3 163--191 Abstract The theory of wavelets has recently undergone the statistical language S to perform one and twodimensional discrete wavelet transforms. The transforms
The Discrete Wavelet Transform in S G. P. Nason and B. W. Silvermany
Nason, Guy
The Discrete Wavelet Transform in S G. P. Nason and B. W. Silvermany Journal of Computational and Graphical Statistics 1994 3 163 191 Abstract The theory of wavelets has recently undergone a period of rapid language S to perform one- and two-dimensional discrete wavelet transforms. The transforms
Discrete ultrahigh-pressure domains in the Western Gneiss Region, Norway: implications for formation and exhumation
Hacker, Bradley R.
Discrete ultrahigh-pressure domains in the Western Gneiss Region, Norway: implications of Norway, Leiv Erikssons vei 39, 7491 Trondheim, Norway 4 Division of Geological and Planetary Sciences Ar ages within the Western Gneiss Region of Norway define three discrete ultrahigh-pressure (UHP
A Mixed Finite-Element Discretization of the Energy-Transport Model for Semiconductors
Pietra, Paola
A Mixed Finite-Element Discretization of the Energy-Transport Model for Semiconductors Stefan Holst #12;tting mixed #12;nite-element method is used to discretize the stationary energy. Energy-transport models describe the ow of electrons through a semi- conductor device, in uenced by di
Convergence of the Approximation Scheme to American Option Pricing via the Discrete Morse Semiflow
Ishii, Katsuyuki, E-mail: firstname.lastname@example.com [Kobe University, Graduate School of Maritime Sciences (Japan); Omata, Seiro, E-mail: firstname.lastname@example.com [Kanazawa University, School of Mathematics and Physics, Institute of Science and Engineering (Japan)
We consider the approximation scheme to the American call option via the discrete Morse semiflow, which is a minimizing scheme of a time semi-discretized variational functional. In this paper we obtain a rate of convergence of approximate solutions and the convergence of approximate free boundaries. We mainly apply the theory of variational inequalities and that of viscosity solutions to prove our results.
Improving behavioral realism in hybrid energy-economy models using discrete choice
Improving behavioral realism in hybrid energy-economy models using discrete choice studies Abstract Hybrid energy-economy models combine top-down and bottom-up approaches to explore behaviorally models to inform key behavioral parameters in CIMS, a hybrid model. The discrete choice models
Thermodynamics and phase transitions of electrolytes on lattices with different discretization parameters
Thermodynamics and phase transitions of electrolytes on lattices with different discretization February 2005; in final form 14 April 2005) Lattice models are crucial for studying thermodynamic thermodynamics and the nature of phase transitions in systems with charged particles. A discretization parameter
Linear diffusion-wave channel routing using a discrete Hayami convolution method
method that neglects the acceleration terms, and the kinematic-wave method that neglects bothLinear diffusion-wave channel routing using a discrete Hayami convolution method Li Wang a, , Joan-in-Chief, with the assistance of Baxter E. Vieux, Associate Editor Keywords: Linear diffusion-wave channel routing Discrete
An Exposition of Structural Estimation of Discrete Dynamic Decision Processes1
Provencher, R. William
An Exposition of Structural Estimation of Discrete Dynamic Decision Processes1 Bill Provencher, Springer 2005. 1 #12;An Exposition of Structural Estimation of Discrete Dynamic Decision Processes I economists directly employed their structural dynamic models in the pursuit of the positive question, What
Discrete thermal element modelling of heat conduction in particle systems: Basic formulations
Martin, Ralph R.
methodology, termed the discrete thermal element method (DTEM), for the effec- tive modelling of heat rights reserved. Keywords: Discrete thermal element method; Circular particle; Thermal contact; Heat conduction; Boundary (integral) equation/element 1. Introduction Heat transfer in particle systems can
Discrete-time Lyapunov based small-gain theorem for parameterized interconnected ISS systems
Nesic, Dragan
Discrete-time Lyapunov based small-gain theorem for parameterized interconnected ISS systems Dina via the Lyapunov method. In particular, an ISS Lyapunov function for the overall system is constructed from the ISS Lyapunov functions of the two subsystems. We consider parameterized families of discrete
Conditions of Employment Modern Apprentice
Strathclyde, University of
Conditions of Employment Modern Apprentice 1. GENERAL CONDITIONS Members of staff are subject. Modern Apprentices are required under this agreement to undertake training, attend courses and carry out
New nonlinear mechanisms of midlatitude atmospheric low-frequency variability
and Atmospheric Research Utrecht, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands Abstract
Clathrate hydrates as a sink of noble gases in Titan's atmosphere
Thomas, C; Ballenegger, V; Picaud, Sylvain
We use a statistical thermodynamic approach to determine the composition of clathrate hydrates which may form from a multiple compound gas whose composition is similar to that of Titan's atmosphere. Assuming that noble gases are initially present in this gas phase, we calculate the ratios of xenon, krypton and argon to species trapped in clathrate hydrates. We find that these ratios calculated for xenon and krypton are several orders of magnitude higher than in the coexisting gas at temperature and pressure conditions close to those of Titan's present atmosphere at ground level. Furthermore we show that, by contrast, argon is poorly trapped in these ices. This trapping mechanism implies that the gas-phase is progressively depleted in xenon and krypton when the coexisting clathrate hydrates form whereas the initial abundance of argon remains almost constant. Our results are thus compatible with the deficiency of Titan's atmosphere in xenon and krypton measured by the {\\it Huygens} probe during its descent on J...
Atmospheric and Wake Turbulence Impacts on Wind Turbine Fatigue Loading: Preprint
Lee, S.; Churchfield, M.; Moriarty, P.; Jonkman, J.; Michalakes, J.
Large-eddy simulations of atmospheric boundary layers under various stability and surface roughness conditions are performed to investigate the turbulence impact on wind turbines. In particular, the aeroelastic responses of the turbines are studied to characterize the fatigue loading of the turbulence present in the boundary layer and in the wake of the turbines. Two utility-scale 5 MW turbines that are separated by seven rotor diameters are placed in a 3 km by 3 km by 1 km domain. They are subjected to atmospheric turbulent boundary layer flow and data is collected on the structural response of the turbine components. The surface roughness was found to increase the fatigue loads while the atmospheric instability had a small influence. Furthermore, the downstream turbines yielded higher fatigue loads indicating that the turbulent wakes generated from the upstream turbines have significant impact.
An advanced open-path atmospheric pollution monitor for large areas
Taylor, L.
Large amounts of toxic waste materials, generated in manufacturing fuel for nuclear reactors, are stored in tanks buried over large areas at DOE sites. Flammable and hazardous gases are continually generated by chemical reactions in the waste materials. To prevent explosive concentrations of these gases, the gases are automatically vented to the atmosphere when the pressure exceeds a preset value. Real-time monitoring of the atmosphere above the tanks with automatic alarming is needed to prevent exposing workers to unsafe conditions when venting occurs. This project is to design, develop, and test an atmospheric pollution monitor which can measure concentrations of DOE-specified and EPA-specified hazardous gases over ranges as long as 4km. A CO{sub 2} laser to measure absorption spectra and to determine the distance over which the measurements are made, is combined with an acousto-optic tunable filter (AOTF) to measure thermal emission spectra.
Discrete Event Modeling of Algae Cultivation and Harvesting at Commercial Scale: Capital Costs, Operating Costs, and System Bottlenecks
Lacey, Ph.D, P.E., Ronald E. [Texas A& M University
Discrete Event Modeling of Algae Cultivation and Harvesting at Commercial Scale: Capital Costs, Operating Costs, and System Bottlenecks
Pulsed atmospheric fluidized-bed combustor development. Environmental Assessment
Not Available
Pulsed atmospheric fluidized-bed combustion (PAFBC) is a unique and innovative coal-fueled technology that has the potential to meet these conditions and provide heat and/or process steam to small industrial, commercial, institutional and residential complexes. The potential of Pulse Atmospheric Fluidized Bed Combustion (PAFBC) technology has been amply demonstrated under the sponsorship of a previous DOE/METC contract (DE-AC21-88MC25069). The environmental performance of a coal-fired laboratory-scale system (1.5 million British Thermal Units per hour) (MMBtu/hr) significantly surpassed that of conventional bubbling and circulating fluidized-bed combustion units (see Table 1 for performance comparison). Prompted by these encouraging results in combustion, sulfur capture, emissions control, and enhanced heat transfer, Island Creek Coal Company (ICC) and Baltimore Thermal Energy Corporation expressed interest in the technology and offered to participate by providing host sites for field testing. EA`s have been submitted independently for each of these field test sites. This submission addresses the preliminary testing of the PAFBC unit at Manufacturing and Technology Conversion International`s (MTCI) Baltimore, MD facility.
Calibration of LSST Instrumental and Atmospheric Photometric Passbands
Burke, David L.; /SLAC; Axelrod, T.; /Arizona U., Astron. Dept. - Steward Observ.; Barrau, Aurelien; Baumont, Sylvain; /LPSC, Grenoble; Blondin, Stephane; /Marseille, CPPM; Claver, Chuck; /NOAO, Tucson; Gorecki, Alexia; /LPSC, Grenoble; Ivezic, Zeljko; Jones, Lynne; /Washington U., Seattle, Astron. Dept.; Krabbendam, Victor; Liang, Ming; Saha, Abhijit; /NOAO, Tucson; Smith, Allyn; /Austin Peay State U.; Smith, R.Chris; /Cerro-Tololo InterAmerican Obs.; Stubbs, Christopher W.; /Harvard-Smithsonian Ctr. Astrophys.
The Large Synoptic Survey Telescope (LSST) will continuously image the entire sky visible from Cerro Pachon in northern Chile every 3-4 nights throughout the year. The LSST will provide data for a broad range of science investigations that require better than 1% photometric precision across the sky (repeatability and uniformity) and a similar accuracy of measured broadband color. The fast and persistent cadence of the LSST survey will significantly improve the temporal sampling rate with which celestial events and motions are tracked. To achieve these goals, and to optimally utilize the observing calendar, it will be necessary to obtain excellent photometric calibration of data taken over a wide range of observing conditions - even those not normally considered 'photometric'. To achieve this it will be necessary to routinely and accurately measure the full optical passband that includes the atmosphere as well as the instrumental telescope and camera system. The LSST mountain facility will include a new monochromatic dome illumination projector system to measure the detailed wavelength dependence of the instrumental passband for each channel in the system. The facility will also include an auxiliary spectroscopic telescope dedicated to measurement of atmospheric transparency at all locations in the sky during LSST observing. In this paper, we describe these systems and present laboratory and observational data that illustrate their performance.
Atmospheric Circulation and Tides of "51Peg b-like" Planets
Adam P. Showman; Tristan Guillot
We examine the properties of the atmospheres of extrasolar giant planets at orbital distances smaller than 0.1 AU from their stars. We show that these ``51Peg b-like'' planets are rapidly synchronized by tidal interactions, but that small departures from synchronous rotation can occur because of fluid-dynamical torques within these planets. Previous radiative-transfer and evolution models of such planets assume a homogeneous atmosphere. Nevertheless, we show using simple arguments that, at the photosphere, the day-night temperature difference and characteristic wind speeds may reach ~500 K and ~2 km/s, respectively. Substantial departures from chemical equilibrium are expected. The cloud coverage depends sensitively on the dynamics; clouds could exist predominantly either on the dayside or nightside, depending on the circulation regime. Radiative-transfer models that assume homogeneous conditions are therefore inadequate in describing the atmospheric properties of 51Peg b-like planets. We present preliminary three-dimensional, nonlinear simulations of the atmospheric circulation of HD209458b that indicate plausible patterns for the circulation and generally agree with our simpler estimates. Furthermore, we show that kinetic energy production in the atmosphere can lead to the deposition of substantial energy in the interior, with crucial consequences for the evolution of these planets. Future measurements of reflected and thermally-emitted radiation from these planets will help test our ideas.
A Simplex Cut-Cell Adaptive Method for High-Order Discretizations of the Compressible Navier-Stokes Equations
Peraire, Jaime
A Simplex Cut-Cell Adaptive Method for High-Order Discretizations of the Compressible Navier;A Simplex Cut-Cell Adaptive Method for High-Order Discretizations of the Compressible Navier adaptation for high-order discretizations and simplex, cut-cell mesh generation. First, output-based mesh
IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 54, NO. 11, NOVEMBER 2006 4261 Discrete Generalized Fresnel Functions and
Aizenberg, Igor
Fresnel Functions and Transforms in an Arbitrary Discrete Basis Igor Aizenberg, Senior Member, IEEE, and Jaakko T. Astola, Fellow, IEEE Abstract--The idea of generalized Fresnel functions, which traces back discrete Fresnel functions and the generalized discrete Fresnel transforms for an arbitrary basis
Conditional sterility in plants
Meagher, Richard B. (Athens, GA); McKinney, Elizabeth (Athens, GA); Kim, Tehryung (Taejeon, KR)
The present disclosure provides methods, recombinant DNA molecules, recombinant host cells containing the DNA molecules, and transgenic plant cells, plant tissue and plants which contain and express at least one antisense or interference RNA specific for a thiamine biosynthetic coding sequence or a thiamine binding protein or a thiamine-degrading protein, wherein the RNA or thiamine binding protein is expressed under the regulatory control of a transcription regulatory sequence which directs expression in male and/or female reproductive tissue. These transgenic plants are conditionally sterile; i.e., they are fertile only in the presence of exogenous thiamine. Such plants are especially appropriate for use in the seed industry or in the environment, for example, for use in revegetation of contaminated soils or phytoremediation, especially when those transgenic plants also contain and express one or more chimeric genes which confer resistance to contaminants.
Magnetized Atmospheres around Accreting Neutron Stars
S. Zane; R. Turolla; A. Treves
We present a detailed investigation of atmospheres around accreting neutron stars with high magnetic field ($B\\gtrsim 10^{12}$ G) and low luminosity ($L\\lesssim 10^{33}$ erg/s). We compute the atmospheric structure, intensity and emergent spectrum for a plane-parallel, pure hydrogen medium by solving the transfer equations for the normal modes coupled to the hydrostatic and energy balance equations. The hard tail found in previous investigations for accreting, non-magnetic neutron stars with comparable luminosity is suppressed and the X-ray spectrum, although still harder than a blackbody at the star effective temperature, is nearly planckian in shape. Spectra from accreting atmospheres, both with high and low fields, are found to exhibit a significant excess at optical wavelengths above the Rayleigh-Jeans tail of the X-ray continuum.
Atmospheric Pressure Plasma Process And Applications
Peter C. Kong; Myrtle
This paper provides a general discussion of atmospheric-pressure plasma generation, processes, and applications. There are two distinct categories of atmospheric-pressure plasmas: thermal and nonthermal. Thermal atmospheric-pressure plasmas include those produced in high intensity arcs, plasma torches, or in high intensity, high frequency discharges. Although nonthermal plasmas are at room temperatures, they are extremely effective in producing activated species, e.g., free radicals and excited state atoms. Thus, both thermal and nonthermal atmosphericpressure plasmas are finding applications in a wide variety of industrial processes, e.g. waste destruction, material recovery, extractive metallurgy, powder synthesis, and energy conversion. A brief discussion of recent plasma technology research and development activities at the Idaho National Laboratory is included.
Super Kamiokande results: atmospheric and solar neutrinos
M. Ishitsuka; for the Super-Kamiokande Collaboration
Atmospheric neutrino and solar neutrino data from the first phase of Super-Kamiokande (SK-I) are presented. The observed data are used to study atmospheric and solar neutrino oscillations. Zenith angle distributions from various atmospheric neutrino data samples are used to estimate the neutrino oscillation parameter region. In addition, a new result of the $L/E$ measurement is presented. A dip in the $L/E$ distribution was observed in the data, as predicted from the sinusoidal flavor transition probability of neutrino oscillation. The energy spectrum and the time variation such as day/night and seasonal differences of solar neutrino flux are measured in Super-Kamiokande. The neutrino oscillation parameters are strongly constrained from those measurements.
E. Siegmann
The purpose of this analysis is to describe the condition of commercial Zircaloy clad fuel as it is received at the Yucca Mountain Project (YMP) site. Most commercial nuclear fuel is encased in Zircaloy cladding. This analysis is developed to describe cladding degradation from the expected failure modes. This includes reactor operation impacts including incipient failures, potential degradation after reactor operation during spent fuel storage in pool and dry storage and impacts due to transportation. Degradation modes include cladding creep, and delayed hydride cracking during dry storage and transportation. Mechanical stresses from fuel handling and transportation vibrations are also included. This Analysis and Model Report (AMR) does not address any potential damage to assemblies that might occur at the YMP surface facilities. Ranges and uncertainties have been defined. This analysis will be the initial boundary condition for the analysis of cladding degradation inside the repository. In accordance with AP-2.13Q, ''Technical Product Development Planning'', a work plan (CRWMS M&O 2000c) was developed, issued, and utilized in the preparation of this document. There are constraints, caveats and limitations to this analysis. This cladding degradation analysis is based on commercial Pressurized Water Reactor (PWR) fuel with Zircaloy cladding but is applicable to Boiling Water Reactor (BWR) fuel. Reactor operating experience for both PWRs and BWRs is used to establish fuel reliability from reactor operation. It is limited to fuel exposed to normal operation and anticipated operational occurrences (i.e. events which are anticipated to occur within a reactor lifetime), and not to fuel that has been exposed to severe accidents. Fuel burnup projections have been limited to the current commercial reactor licensing environment with restrictions on fuel enrichment, oxide coating thickness and rod plenum pressures. The information provided in this analysis will be used in evaluating the post-closure performance of the Monitored Geologic Repository (MGR) in relation to waste form degradation.
Contamination of Dark Matter Experiments from Atmospheric Magnetic Dipoles
A. Bueno; M. Masip; P. S�nchez-Lucas; N. Setzer
Dark matter collisions with heavy nuclei (Xe, Ge, Si, Na) may produce recoils observable at direct-search experiments. Given that some of these experiments are yielding conflicting information, however, it is worth asking if physics other than dark matter may produce similar nuclear recoils. We examine under what conditions an atmospherically-produced neutral particle with a relatively large magnetic dipole moment could fake a dark matter signal. We argue that a very definite flux could explain the signals seen at DAMA/LIBRA, CDMS/Si and CoGeNT consistently with the bounds from XENON100 and CDMS/Ge. To explore the plausibility of this scenario, we discuss a concrete model with 10-50 MeV sterile neutrinos that was recently proposed to explain the LSND and MiniBooNE anomalies.
Optical emission spectroscopy of atmospheric pressure microwave plasmas
Jia Haijun; Fujiwara, Hiroyuki; Kondo, Michio [Research Center for Photovoltaics (RCPVs), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Kuraseko, Hiroshi [Furukawa Electric Co., Ltd., Production Technology Development Center, 6 Yawata-Kaigandori, Chiba 290-8555 (Japan)
The optical emission behaviors of Ar, He, and Ar+He plasmas generated in air using an atmospheric pressure microwave plasma source have been studied employing optical emission spectroscopy (OES). Emissions from various source gas species and air were observed. The variations in the intensities and intensity ratios of specific emissions as functions of the microwave power and gas flow rate were analyzed to investigate the relationship between the emission behavior and the plasma properties. We find that dependence of the emission behavior on the input microwave power is mainly determined by variations in electron density and electron temperature in the plasmas. On the other hand, under different gas flow rate conditions, changes in the density of the source gas atoms also significantly affect the emissions. Interestingly, when plasma is generated using an Ar+He mixture, emissions from excited He atoms disappear while a strong H{sub {alpha}} signal appears. The physics behind these behaviors is discussed in detail.
Controlled Microdroplet Transport in an Atmospheric Pressure Microplasma
Maguire, P D; Kelsey, C P; Bingham, A; Montgomery, E P; Bennet, E D; Potts, H E; Rutherford, D; McDowell, D A; Diver, D A; Mariotti, D
We report the controlled injection of near-isolated micron-sized liquid droplets into a low temperature He-Ne steady-state rf plasma at atmospheric pressure. The H2O droplet stream is constrained within a 2 mm diameter quartz tube. Imaging at the tube exit indicates a log-normal droplet size distribution with an initial count mean diameter of 15 micrometers falling to 13 micrometers with plasma exposure. The radial velocity profile is approximately parabolic indicating near laminar flow conditions with the majority of droplets travelling at >75% of the local gas speed and having a plasma transit time of < 100 microseconds. The maximum gas temperature, determined from nitrogen spectral lines, was below 400 K and the observed droplet size reduction implies additional factors beyond standard evaporation, including charge and surface chemistry effects. The successful demonstration of controlled microdroplet streams opens up possibilities for gas-phase microreactors and remote delivery of active species for pla...
Phenomena of oscillations in atmospheric pressure direct current glow discharges
Liu, Fu-cheng [College of Physics Science and Technology, Hebei University, Baoding 071002 (China)] [College of Physics Science and Technology, Hebei University, Baoding 071002 (China); Yan, Wen; Wang, De-zhen [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
Self-sustained oscillations in a dc glow discharge with a semiconductor layer at atmospheric pressure were investigated by means of a one-dimensional fluid model. It is found that the dc glow discharge initially becomes unstable in the subnormal glow region and gives rise to oscillations of plasma parameters. A variety of oscillations with one or more frequencies have been observed under different conditions. The discharge oscillates between the glow discharge mode and the Townsend discharge mode in the oscillations with large amplitude while operates in the subnormal glow discharge mode all the while in the oscillations with small amplitude. Fourier Transform spectra of oscillations reveal the transition mechanism between different oscillations. The effects of semiconductor conductivity on the oscillation frequency of the dominant mode, gas voltage, as well as the discharge current have also been analyzed.
A Community Atmosphere Model with Superparameterized Clouds
Randall, David; Branson, Mark; Wang, Minghuai; Ghan, Steven J.; Craig, Cheryl; Gettelman, A.; Edwards, Jim
In 1999, National Center for Atmospheric Research (NCAR) scientists Wojciech Grabowski and Piotr Smolarkiewicz created a "multiscale" atmospheric model in which the physical processes associated with clouds were represented by running a simple high-resolution model within each grid column of a lowresolution global model. In idealized experiments, they found that the multiscale model produced promising simulations of organized tropical convection, which other models had struggled to produce. Inspired by their results, Colorado State University (CSU) scientists Marat Khairoutdinov and David Randall created a multiscale version of the Community Atmosphere Model (CAM). They removed the cloud parameterizations of the CAM, and replaced them with Khairoutdinov's high-resolution cloud model. They dubbed the embedded cloud model a "super-parameterization," and the modified CAM is now called the "SP-CAM." Over the next several years, many scientists, from many institutions, have explored the ability of the SP-CAM to simulate tropical weather systems, the day-night changes of precipitation, the Asian and African monsoons, and a number of other climate processes. Cristiana Stan of the Center for Ocean-Land-Atmosphere Interactions found that the SP-CAM gives improved results when coupled to an ocean model, and follow-on studies have explored the SP-CAM's utility when used as the atmospheric component of the Community Earth System Model. Much of this research has been performed under the auspices of the Center for Multiscale Modeling of Atmospheric Processes, a National Science Foundation (NSF) Science and Technology Center for which the lead institution is CSU.
Measuring Atmospheric Neutrino Oscillations with Neutrino Telescopes
Ivone F. M. Albuquerque; George F. Smoot
Neutrino telescopes with large detection volumes can demonstrate that the current indications of neutrino oscillation are correct or if a better description can be achieved with non-standard alternatives. Observations of contained muons produced by atmospheric neutrinos can better constrain the allowed region for oscillations or determine the relevant parameters of non-standard models. We analyze the possibility of neutrino telescopes measuring atmospheric neutrino oscillations. We suggest adjustments to improve this potential. An addition of four densely-instrumented strings to the AMANDA II detector makes observations feasible. Such a configuration is competitive with current and proposed experiments.
Controlled atmosphere for fabrication of cermet electrodes
Ray, S.P.; Woods, R.W.
A process is disclosed for making an inert electrode composite wherein a metal oxide and a metal are reacted in a gaseous atmosphere at an elevated temperature of at least about 750 C. The metal oxide is at least one of the nickel, iron, tin, zinc and zirconium oxides and the metal is copper, silver, a mixture of copper and silver or a copper-silver alloy. The gaseous atmosphere has an oxygen content that is controlled at about 5--3000 ppm in order to obtain a desired composition in the resulting composite. 2 figs.
Controlled atmosphere for fabrication of cermet electrodes
Ray, Siba P. (Murrysville, PA); Woods, Robert W. (New Kensington, PA)
A process for making an inert electrode composite wherein a metal oxide and a metal are reacted in a gaseous atmosphere at an elevated temperature of at least about 750.degree. C. The metal oxide is at least one of the nickel, iron, tin, zinc and zirconium oxides and the metal is copper, silver, a mixture of copper and silver or a copper-silver alloy. The gaseous atmosphere has an oxygen content that is controlled at about 5-3000 ppm in order to obtain a desired composition in the resulting composite.
A discrete analogue of periodic delta Bose gas and affine Hecke algebra
Yoshihiro Takeyama
We consider an eigenvalue problem for a discrete analogue of the Hamiltonian of the non-ideal Bose gas with delta-potentials on a circle. It is a two-parameter deformation of the discrete Hamiltonian for joint moments of the partition function of the O'Connell-Yor semi-discrete polymer. We construct the propagation operator by using integral-reflection operators, which give a representation of the affine Hecke algebra. We also construct eigenfunctions by means of the Bethe ansatz method.
Inverse scattering transform for the focusing nonlinear Schr�dinger equation with nonzero boundary conditions
Biondini, Gino [Department of Mathematics, State University of New York at Buffalo, Buffalo, New York 14260 (United States)] [Department of Mathematics, State University of New York at Buffalo, Buffalo, New York 14260 (United States); Kova?i?, Gregor [Department of Mathematical Sciences, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)] [Department of Mathematical Sciences, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)
The inverse scattering transform for the focusing nonlinear Schr�dinger equation with non-zero boundary conditions at infinity is presented, including the determination of the analyticity of the scattering eigenfunctions, the introduction of the appropriate Riemann surface and uniformization variable, the symmetries, discrete spectrum, asymptotics, trace formulae and the so-called theta condition, and the formulation of the inverse problem in terms of a Riemann-Hilbert problem. In addition, the general behavior of the soliton solutions is discussed, as well as the reductions to all special cases previously discussed in the literature.
Atmospheric performance of the special-purpose Solar Energy Research Institute (SERI) thin-airfoil family
Tangler, J; Smith, B; Jager, D; Olsen, T
The Solar Energy Research Institute (SERI), in cooperation with SeaWest Energy Group, has completed extensive atmospheric testing of the special-purpose SERI thin-airfoil family during the 1990 wind season. The purpose of this test program was to experimentally verify the predicted performance characteristics of the thin-airfoil family on a geometrically optimized blade, and to compare it to original-equipment blades under atmospheric wind conditions. The tests were run on two identical Micon 65/13 horizontal-axis wind turbines installed side-by-side in a wind farm. The thin-airfoil family 7.96 m blades were installed on one turbine, and AeroStar 7.41 m blades were installed on the other. This paper presents final performance results of the side-by-side comparative field test for both clean and dirty blade conditions. 7 refs., 11 figs., 1 tab.
Non-Abelian discrete gauge symmetries in F-theory
Thomas W. Grimm; Tom G. Pugh; Diego Regalado
The presence of non-Abelian discrete gauge symmetries in four-dimensional F-theory compactifications is investigated. Such symmetries are shown to arise from seven-brane configurations in genuine F-theory settings without a weak string coupling description. Gauge fields on mutually non-local seven-branes are argued to gauge both R-R and NS-NS two-form bulk axions. The gauging is completed into a generalisation of the Heisenberg group with either additional seven-brane gauge fields or R-R bulk gauge fields. The former case relies on having seven-brane fluxes, while the latter case requires torsion cohomology and is analysed in detail through the M-theory dual. Remarkably, the M-theory reduction yields an Abelian theory that becomes non-Abelian when translated into the correct duality frame to perform the F-theory limit. The reduction shows that the gauge coupling function depends on the gauged scalars and transforms non-trivially as required for the groups encountered. This field dependence agrees with the expectations for the kinetic mixing of seven-branes and is unchanged if the gaugings are absent.
Discrete-Time ARMAv Model-Based Optimal Sensor Placement
Song Wei; Dyke, Shirley J. [Washington University in St. Louis, St. Louis, MO 63130 (United States)
This paper concentrates on the optimal sensor placement problem in ambient vibration based structural health monitoring. More specifically, the paper examines the covariance of estimated parameters during system identification using auto-regressive and moving average vector (ARMAv) model. By utilizing the discrete-time steady state Kalman filter, this paper realizes the structure's finite element (FE) model under broad-band white noise excitations using an ARMAv model. Based on the asymptotic distribution of the parameter estimates of the ARMAv model, both a theoretical closed form and a numerical estimate form of the covariance of the estimates are obtained. Introducing the information entropy (differential entropy) measure, as well as various matrix norms, this paper attempts to find a reasonable measure to the uncertainties embedded in the ARMAv model estimates. Thus, it is possible to select the optimal sensor placement that would lead to the smallest uncertainties during the ARMAv identification process. Two numerical examples are provided to demonstrate the methodology and compare the sensor placement results upon various measures.
Entrainment of coarse grains using a discrete particle model
Valyrakis, Manousos, E-mail: email@example.com [Lecturer in Water and Environmental Engineering, Rankine 817b, University of Glasgow, Glasgow G12 8LT (United Kingdom); Arnold, Roger B. Jr. [Environmental Engineer, Arcadis, USA (formerly: research assistant Virginia Tech, USA) (United States)
Conventional bedload transport models and incipient motion theories relying on a time-averaged boundary shear stress are incapable of accounting for the effects of fluctuating near-bed velocity in turbulent flow and are therefore prone to significant errors. Impulse, the product of an instantaneous force magnitude and its duration, has been recently proposed as an appropriate criterion for quantifying the effects of flow turbulence in removing coarse grains from the bed surface. Here, a discrete particle model (DPM) is used to examine the effects of impulse, representing a single idealized turbulent event, on particle entrainment. The results are classified according to the degree of grain movement into the following categories: motion prior to entrainment, initial dislodgement, and energetic displacement. The results indicate that in all three cases the degree of particle motion depends on both the force magnitude and the duration of its application and suggest that the effects of turbulence must be adequately accounted for in order to develop a more accurate method of determining incipient motion. DPM is capable of simulating the dynamics of grain entrainment and is an appropriate tool for further study of the fundamental mechanisms of sediment transport.
Non-Abelian discrete gauge symmetries in F-theory
Grimm, Thomas W; Regalado, Diego
The presence of non-Abelian discrete gauge symmetries in four-dimensional F-theory compactifications is investigated. Such symmetries are shown to arise from seven-brane configurations in genuine F-theory settings without a weak string coupling description. Gauge fields on mutually non-local seven-branes are argued to gauge both R-R and NS-NS two-form bulk axions. The gauging is completed into a generalisation of the Heisenberg group with either additional seven-brane gauge fields or R-R bulk gauge fields. The former case relies on having seven-brane fluxes, while the latter case requires torsion cohomology and is analysed in detail through the M-theory dual. Remarkably, the M-theory reduction yields an Abelian theory that becomes non-Abelian when translated into the correct duality frame to perform the F-theory limit. The reduction shows that the gauge coupling function depends on the gauged scalars and transforms non-trivially as required for the groups encountered. This field dependence agrees with the exp...
Thermal Neutron Detectors with Discrete Anode Pad Readout
Yu,B.; Schaknowski, N.A., Smith, G.C., DeGeronimo, G., Vernon, E.O.
A new two-dimensional thermal neutron detector concept that is capable of very high rates is being developed. It is based on neutron conversion in {sup 3}He in an ionization chamber (unity gas gain) that uses only a cathode and anode plane; there is no additional electrode such as a Frisch grid. The cathode is simply the entrance window, and the anode plane is composed of discrete pads, each with their own readout electronics implemented via application specific integrated circuits. The aim is to provide a new generation of detectors with key characteristics that are superior to existing techniques, such as higher count rate capability, better stability, lower sensitivity to background radiation, and more flexible geometries. Such capabilities will improve the performance of neutron scattering instruments at major neutron user facilities. In this paper, we report on progress with the development of a prototype device that has 48 x 48 anode pads and a sensitive area of 24cm x 24cm.
Metrics for Availability Analysis Using a Discrete Event Simulation Method
Schryver, Jack C [ORNL; Nutaro, James J [ORNL; Haire, Marvin Jonathan [ORNL
The system performance metric 'availability' is a central concept with respect to the concerns of a plant's operators and owners, yet it can be abstract enough to resist explanation at system levels. Hence, there is a need for a system-level metric more closely aligned with a plant's (or, more generally, a system's) raison d'etre. Historically, availability of repairable systems - intrinsic, operational, or otherwise - has been defined as a ratio of times. This paper introduces a new concept of availability, called endogenous availability, defined in terms of a ratio of quantities of product yield. Endogenous availability can be evaluated using a discrete event simulation analysis methodology. A simulation example shows that endogenous availability reduces to conventional availability in a simple series system with different processing rates and without intermediate storage capacity, but diverges from conventional availability when storage capacity is progressively increased. It is shown that conventional availability tends to be conservative when a design includes features, such as in - process storage, that partially decouple the components of a larger system.
Lossy compression of discrete sources via Viterbi algorithm
Jalali, Shirin; Weissman, Tsachy
We present a new lossy compressor for discrete-valued sources. For coding a sequence $x^n$, the encoder starts by assigning a certain cost to each possible reconstruction sequence. It then finds the one that minimizes this cost and describes it losslessly to the decoder via a universal lossless compressor. The cost of each sequence is a linear combination of its distance from the sequence $x^n$ and a linear function of its $k^{\\rm th}$ order empirical distribution. The structure of the cost function allows the encoder to employ the Viterbi algorithm to recover the minimizer of the cost. We identify a choice of the coefficients comprising the linear function of the empirical distribution used in the cost function which ensures that the algorithm universally achieves the optimum rate-distortion performance of any stationary ergodic source in the limit of large $n$, provided that $k$ diverges as $o(\\log n)$. Iterative techniques for approximating the coefficients, which alleviate the computational burden of find...
Lattice Gauge Fields and Discrete Noncommutative Yang-Mills Theory
J. Ambjorn; Y. M. Makeenko; J. Nishimura; R. J. Szabo
We present a lattice formulation of noncommutative Yang-Mills theory in arbitrary even dimensionality. The UV/IR mixing characteristic of noncommutative field theories is demonstrated at a completely nonperturbative level. We prove a discrete Morita equivalence between ordinary Yang-Mills theory with multi-valued gauge fields and noncommutative Yang-Mills theory with periodic gauge fields. Using this equivalence, we show that generic noncommutative gauge theories in the continuum can be regularized nonperturbatively by means of {\\it ordinary} lattice gauge theory with 't~Hooft flux. In the case of irrational noncommutativity parameters, the rank of the gauge group of the commutative lattice theory must be sent to infinity in the continuum limit. As a special case, the construction includes the recent description of noncommutative Yang-Mills theories using twisted large $N$ reduced models. We study the coupling of noncommutative gauge fields to matter fields in the fundamental representation of the gauge group using the lattice formalism. The large mass expansion is used to describe the physical meaning of Wilson loops in noncommutative gauge theories. We also demonstrate Morita equivalence in the presence of fundamental matter fields and use this property to comment on the calculation of the beta-function in noncommutative quantum electrodynamics.
Discreteness effects in cosmological N-body simulations
James Binney
An estimate of the convergence radius of a simulated CDM halo is obtained under the assumption that the peak phase-space density in the system is set by discreteness effects that operate prior to relaxation. The predicted convergence radii are approximately a factor 2 larger than those estimated for numerical convergence studies. A toy model is used to study the formation of sheets of the cosmic web, from which DM haloes form later. This model demonstrates the interplay between phase mixing and violent relaxation that must also be characteristic of spherical collapse. In the limit that sheets contain arbitrarily many particles, it seems that power-law profiles are established in both distance and energy. When only a finite number of particles is employed, relaxation is prematurely terminated and the power laws are broken. In a given simulation, the sheets with the highest peak phase-space densities are those that form from the longest waves. Hence simulations with little small-scale power are expected to form the cuspiest haloes.
Semiclassical energy conditions and wormholes
Prado Martin-Moruno
We consider the nonlinear energy conditions and their quantum extensions. These new energy conditions behave much better than the usual pointwise energy conditions in the presence of semiclassical quantum effects. Analogous quantum extensions for the linear energy conditions are not always satisfied as one enters the quantum realm, but they can be used to constrain the violation of the classical conditions. Thus, the existence of wormholes supported by a fluid which violates the null energy condition in a controlled way is of particular interest.
Processing materials inside an atmospheric-pressure radiofrequency nonthermal plasma discharge
Selwyn, Gary S.; Henins, Ivars; Park, Jaeyoung; Herrmann, Hans W.
Apparatus for the processing of materials involving placing a material either placed between an radio-frequency electrode and a ground electrode, or which is itself one of the electrodes. This is done in atmospheric pressure conditions. The apparatus effectively etches or cleans substrates, such as silicon wafers, or provides cleaning of spools and drums, and uses a gas containing an inert gas and a chemically reactive gas.
Factors affecting the performance of a codisposal atmospheric fluidized-bed combustor
Huang, W.C.
The paper describes the operation of the codisposal atmospheric fluidized-bed combustor (AFBC) installed at Duluth, Minnesota. The facility utilizes refuse-derived fuel to codispose sewage sludge without auxiliary fuel. Operating parameters affecting the combustor performance are discussed with emphasis on temperature distribution, bed fluidization, residence time, freeboard height and flyash properties. Optimum operating conditions are presented and some new concepts and trends of future development in fluidized bed technology are touched on.
Microlensing Effects in Atmospheres of Substars
L. A. Berdina; A. A. Minakov
The purpose of the present work is the study of focusing properties of atmospheres of substars that is necessary for adequate interpreting of observational data and for solving the inverse problem consisting in recovery parameters of 'microlenses' (substars) and sources (quasars). Amplification factor for a quasar image as projected onto the field of microlenses-substars was computed for optical and radio wavelengths.
Atmospheric dispersion in mountain valleys and basins
Allwine, K.J.
The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ventilation rate'' of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.
Atmospheric dispersion in mountain valleys and basins
Allwine, K.J.
The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ``ventilation rate`` of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.
Air Resources Laboratory Atmospheric Tracer Technology
The continuous (near real time) sulfur hexafluoride (SF6 ) analyzers are portable systems that make measurements of atmospheric SF6 concentrations with a response time of just under one second. The rapid response time in Gaussian plume transport and dispersion models. The SF6 analyzers include a computer controlled calibration
1999 Gordon Research Conference on Atmospheric Chemistry
Storm, C.
The Gordon Research Conference (GRC) on Atmospheric Chemistry was held at Salve Regina University in Newport, Rhode Island, June 13-18, 1999. The conference was well attended with 151 participants. The attendees represented the spectrum of endeavor in this field coming from academia, industry, and government laboratories, both US and foreign scientists, senior researchers, young investigators, and students.
Ocean Atmosphere Sea Ice Soil User's Guide
OASIS3 Ocean Atmosphere Sea Ice Soil User's Guide oasis3 prism 2�2, June 2004 Sophie Valcke 1 to realize a coupled simulation with OASIS3. The aim of OASIS3 is to provide a flexible and user friendly. OASIS3 synchronizes the exchanges of coupling fields between the models being coupled, and performs 2D
Ocean Atmosphere Sea Ice Soil User's Guide
OASIS3 Ocean Atmosphere Sea Ice Soil User's Guide oasis3 prism 2�3, August 2004 Sophie Valcke 1 to realize a coupled simulation with OASIS3. The aim of OASIS3 is to provide a flexible and user friendly. OASIS3 synchronizes the exchanges of coupling fields between the models being coupled, and performs 2D
Ocean Atmosphere Sea Ice Soil User's Guide
OASIS 2.0 Ocean Atmosphere Sea Ice Soil User's Guide and Reference Manual November 1995 Laurent for the straightforward use of OASIS 2.0. As far as we know, it is the best way to use it! The aim of OASIS is to provide been particularly emphasized in the OASIS design. The use of OASIS does not change the way the models
Analysis methods for Atmospheric Cerenkov Telescopes
Mathieu de Naurois
Three different analysis techniques for Atmospheric Imaging System are presented. The classical Hillas parameters based technique is shown to be robust and efficient, but more elaborate techniques can improve the sensitivity of the analysis. A comparison of the different analysis techniques shows that they use different information for gamma-hadron separation, and that it is possible to combine their qualities.
Ch.6 Atmospheric and Oceanic Circulations
Pan, Feifei
;Learning Objective Four: Driving forces of wind #12;Driving Forces within the Atmosphere Gravity. #12;Pressure gradient determines wind speed #12; The Coriolis force is an effect of Earth's rotation direction due to the pressure gradient force alone #12;Geostrophic Wind Pressure gradient force + Coriolis
Exploring the Deep... Ocean-Atmosphere
Wright, Dawn Jeannine
Climate oscillations 97 #12;Storing energy To understand how solar radiation affects large-scale processes), and biosphere (living organisms) that are driven by solar energy. The ocean and the atmosphere have the greatest on the others. To fully understand the dynamics of our climate, we must examine the global energy balance
Atmospheric Data Package for the Composite Analysis
Napier, Bruce A.; Ramsdell, James V.
The purpose of this data package is to summarize our conceptual understanding of atmospheric transport and deposition, describe how this understanding will be simplified for numerical simulation as part of the Composite Analysis (i.e., implementation model), and finally to provide the input parameters needed for the simulations.
The mean molecular mass of Titan's atmosphere
Withers, Paul
, Mars, Mars #12;Science Questions � Mean molecular mass (�) -> Chemical composition � How did Titan form? � Current reservoirs of volatiles � Ethane/methane puddles/ocean � Thermal structure of atmosphere #12, delicate, etc � T/p sensors are simple, cheap, reliable � Is it possible to know � based on simple
Characterizing Titan's Upper Atmosphere Using the Titan
Johnson, Robert E.
methane chemical losses. INMS Data T-GITM Bell et al. [2010b] #12;Constraints on Escape � Parameter Sweep-Thermosphere Model (GITM) � 3-D, non-hydrostatic, altitude-based atmospheric model � Compressible Navier (TVD) MUSCL Scheme. � Block-based Massively Parallel Framework � Updating with 4th order Runge
MIDDLE ATMOSPHERE DYNAMICS ATS 708 (3 credits)
Academic Integrity Policy as found in the General Catalog (http://www.catalog.colostate.edu/FrontPDF/1, 1987, Andrews, Holton, Leovy, Academic Press. · Atmospheric and Oceanic Fluid Dynamics, 2006, Vallis Articles (alphabetically): · Baldwin et al., 2001: The quasi-biennial oscillation. Rev. Geophys., 39, 1979
Rutten, Rob
THE LOWER SOLAR ATMOSPHERE ROBERT J. RUTTEN Sterrekundig Instituut, Postbus 80 000, NL�3508 TA, Utrecht, The Netherlands Abstract. This "rapporteur" report discusses the solar photosphere and low does not seem to jeopardize precise determination of solar abundances in classical fashion. It is still
Connectivity To Atmospheric Release Advisory Capability
Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]
To establish DOE and NNSA connectivity to Atmospheric Release Advisory Capability (ARAC) for sites and facilities that have the potential for releasing hazardous materials sufficient to generate certain emergency declarations and to promote efficient use of resources for consequence assessment activities at DOE sites, facilities, operations, and activities in planning for and responding to emergency events. No cancellations.
Propagation of strangelets in the Earth's atmosphere
Fei Wu; Ren-Xin Xu; Bo-Qiang Ma
A new model for the description of the behaviour of strangelets in the Earth's atmosphere is presented. Strangelet fission induced by collision with air nuclei is included. It is shown that strangelets with certain parameters of initial mass and energy may reach depths near sea level, which can be examined by ground-based experiments.
JournalofGeophysicalResearch: Atmospheres RESEARCH ARTICLE
Folkins, Ian
convection to start from more levels � Simple modification of convective parameterization Correspondence to of the Community Atmosphere Model (CAM4), we show that the overall accuracy in the diurnal simulation of convective rise to diurnal cycles in cloud amount [May et al., 2012] and relative humidity [Soden, 2000] which
Land and Atmospheric Science GRAD STUDENT HANDBOOK
Minnesota, University of
, transport, and fate of pollutants in soil, air, and water; improving and protecting land, air, and water, Policy and Management Agricultural Industries and Marketing The Department occupies the entire Soil are predominantly occupied by Soil Morphology and Genesis, Environmental Biophysics, and Atmospheric Sciences, plus
Condition Monitoring System for Reinforced
Painter, Kevin
containing dissolved ionic species such as chlorides. Since concrete is a porous material, with timeCondition Monitoring System for Reinforced Concrete Structures PROBLEM THIS TECHNOLOGY SOLVES: Patent pending concrete condition monitoring system providing `real-time' information on temperature
A theoretical framework for volcanic degassing chemistry in a comparative planetology perspective and implications for planetary atmospheres
Paris-Sud XI, Université de
gases dominated by H2O. This simple pattern broadly mirrors the atmospheres of Venus- Earth of extra-solar planets. Volatile abundances within the planetary body interiors also matter but they play a secondary role. Furthermore, our analysis shows that any difference in redox conditions prevailing during
Algebraic multigrid for stabilized finite element discretizations of the Navier Stokes equation
Okusanya, Tolulope Olawale, 1972 -
A multilevel method for the solution of systems of equations generated by stabilized Finite Element discretizations of the Euler and Navier Stokes equations on generalized unstructured grids is described. The method is ...
Abrams, Aaron
DISCRETIZED CONFIGURATIONS AND PARTIAL PARTITIONS AARON ABRAMS, DAVID GAY, AND VALERIE HOWER to have the homotopy type of a wedge of spheres [2]. 1 #12;2 AARON ABRAMS, DAVID GAY, AND VALERIE HOWER
An Efficient Priority Queue for Large FPGA-Based Discrete Event Simulations of
Herbordt, Martin
: Molecular dynamics simulation based on discrete event simulation (DMD) is emerging as an alternative to time Laboratory Department of Electrical and Computer Engineering Boston University; Boston, MA 02215 Abstract
Testing and examination of TMI-2 electrical components and discrete devices
Soberano, F.T.
This report discusses the approach and results of the in situ test conducted on TMI-2 reactor building electrical components and discrete devices. Also included are the necessary presumptions and assumptions to correlate observed anomalies to the accident.
Intrinsic energy localization through discrete gap breathers in one-dimensional diatomic granular crystals
Theocharis, G.
We present a systematic study of the existence and stability of discrete breathers that are spatially localized in the bulk of a one-dimensional chain of compressed elastic beads that interact via Hertzian contact. The ...
1. The Classical Wavelet Transform for Continuous-time and Discrete-time Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Jansen, Maarten
Contents 1. The Classical Wavelet Transform for Continuous-time and Discrete- time Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 The Continuous Wavelet Transform . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1.1 The Haar wavelet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1
Global Consensus for Discrete-time Multi-Agent Systems with Input Saturation Constraints
Dimarogonas, Dimos
; Yu, Chen, and Cao, 2010; Yang, Roy, Wan, and Saberi, 2011; Seyboth, Dimarogonas, and Johansson, 2013; Grip, Yang, Saberi, and Stoorvogel, 2012). The studies on the discrete-time case are rather limited
F-K Characteristics of the Seismic Response to a Set of Discrete Parallel Fractures
Vetri, Laura
We model seismic wave propagation in a reservoir with discrete fracture zones using a finite difference scheme, which implements the Coates-Schoenberg formulation for fractured media. We study the variation of scattered ...
Paris-Sud XI, Universit� de
A DUALITY APPROACH TO THE GENEALOGIES OF DISCRETE NON-NEUTRAL WRIGHT-FISHER MODELS THIERRY E), there is also some use of the duality concept in an attempt to understand the genealogies of a Wright
From Discrete Space-Time to Minkowski Space: Basic Mechanisms, Methods and Perspectives
Felix Finster
This survey article reviews recent results on fermion system in discrete space-time and corresponding systems in Minkowski space. After a basic introduction to the discrete setting, we explain a mechanism of spontaneous symmetry breaking which leads to the emergence of a discrete causal structure. As methods to study the transition between discrete space-time and Minkowski space, we describe a lattice model for a static and isotropic space-time, outline the analysis of regularization tails of vacuum Dirac sea configurations, and introduce a Lorentz invariant action for the masses of the Dirac seas. We mention the method of the continuum limit, which allows to analyze interacting systems. Open problems are discussed.
Macroscopic behavior and discrete dynamo in high-[Theta] reversed-field pinch discharges
Arimoto, H.; Nakamura, A.; Sato, K.I.; Nagata, A.; Ando, T.; Kubota, S.; Masamune, S.; Nagatsu, M.; Tsukishima, T. (Plasma Science Center, Nagoya University, Chikusa-ku, Nagoya 464-01 (Japan))
The magnetohydrodynamic (MHD) activity and the discrete dynamo in high-[Theta] reversed-field pinch (RFP) discharges are studied through comparisons with those in normal-[Theta] RFP discharges, where [Theta]=[ital B][sub [theta
Matrix-F5 algorithms over finite-precision complete discrete valuation fields
Boyer, Edmond
Matrix-F5 algorithms over finite-precision complete discrete valuation fields Tristan Vaccon that are purely over K, instead of methods over K to solve problems over Q or Fp. Following the works of Taylor